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Cost of Gas Adjustment Factor Rates and Information

The gas supply rate, or Cost of Gas Adjustment factor (GAF), and the Local Distribution Adjustment factor (LDAF) are semiannual rates charged by regulated Massachusetts gas companies.

Table of Contents

Gas Supply Rate/GAF Information

The cost of gas adjustment factor, or GAF, is the rate charged (per therm) by gas companies to recover the cost to buy and transport gas supply to Massachusetts.  If you don't know which gas company serves your location, visit here.

GAF Rate Schedule

Peak period (or winter) rate: November 1 through April 30.

Off-peak period (or summer) rate: May 1 through October 31.

GAF Revisions

While the approved GAFs are meant to cover an entire 6-month period, they may be revised during that time due to the change in the market price for natural gas or other factors.  A gas company may, at any time, submit an amended GAF filing to the Department of Public Utilities (DPU). The gas company must submit the amended GAF filing 7 business days before the first billing cycle of the month in which the new rate would take effect.  220 CMR 6.12. If the DPU approves the amended GAF, we will post an update to this page and label the gas company's GAFs as REVISED. 


LDAF Rate Information

The local distribution adjustment factor, or LDAF, is the rate charged by gas companies to recover costs related to:

For company-specific delivery rate information, including revenue decoupling, go to the DPU's Delivery Rates and Tariffs page.


Historical GAF/LDAF rates and data

For current docket information in the DPU File room, click on the applicable Company listed below.

For GAF and LDAF rates in effect before the 2023/24 peak period, please download the GAF Historical Data Workbook.


Peak/Winter 2023-2024 Rates Revision 2 (Effective 2/1/24 through 4/30/24)

Berkshire Gas CompanyREVISED

Rate Class Billing Unit GAF LDAF
All Residential  $/Therm 0.6648 0.3595
G-41/G-51 $/Therm 0.6648 0.1611
G-42/G-52 $/Therm 0.6648 0.1098
G-43/G-53 $/Therm 0.6648 0.0871
T-54 $/Therm 0.6648 0.0182

 

Eversource Gas Company of Massachusetts (formerly Bay State Gas d/b/a Columbia Gas of Massachusetts)

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 0.5051 0.4339
Residential Heating R-3, R-4 $/Therm 0.6320 0.4339
G-40 $/Therm 0.6320 0.2838
G-41 $/Therm 0.6320 0.2019
G-42 $/Therm 0.6320 0.2032
G-43 $/Therm 0.6320 0.1808
G-50 $/Therm 0.5051 0.2838
G-51 $/Therm 0.5051 0.2019
G-52 $/Therm 0.5051 0.2032
G-53 $/Therm 0.5051 0.1808

 

Fitchburg Gas d/b/a Unitil

Rate Class Billing Unit GAF LDAF Revised LDAF1
Residential Non-Heating R-1, R-2 $/Therm 0.5889 0.7994 0.8090
Residential Heating R-3, R-4 $/Therm 0.6276 0.7994 0.8090
G-41 $/Therm 0.6276 0.5813 0.5903
G-42 $/Therm 0.6276 0.3836 0.3870
G-43 $/Therm 0.6276 0.3245 0.3274
G-51 $/Therm 0.5889 0.5813 0.5903
G-52 $/Therm 0.5889 0.3836 0.3870
G-53 $/Therm 0.5889 0.3245 0.3274

1The LDAF for all rate classes increased on March 1, 2024, which was approved by the Department in Fitchburg Gas and Electric Light Company, D.P.U. 23-156 (February 28, 2024). 

Liberty Utilities - Blackstone (formerly Blackstone Gas Company)

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.2125 0.1671
G-41, G-42, G-43 $/Therm 0.2125 0.0859
G-51, G-52, G-53 $/Therm 0.2125 0.0950

 

Liberty Utilities - North Attleboro/Fall River

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.3737 0.4574
G-41, G-42, G-43 $/Therm 0.3737 0.2743
G-51, G-52, G-53 $/Therm 0.3737 0.2307

 

National Grid - Boston Gas

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.8122 0.4746
G-41B/E, G-51B/E $/Therm 0.8122 0.2548
G-42B/E, G-52B/E $/Therm 0.8122 0.2373
G-43B/E, G-53B/E $/Therm 0.8122 0.2246
G-44B, G-54B $/Therm 0.4452 0.2008
G-44B, G-54B $/MDCQ Therms 5.7297  

 

National Grid - former Colonial Gas

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.8122 0.4077
G-41, G-51 $/Therm 0.8122 0.1869
G-42, G-52 $/Therm 0.8122 0.1793
G-43, G-53 $/Therm 0.8122 0.1530

 

NSTAR Gas Company d/b/a Eversource Energy

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.6712 0.5033
G-41, G-51 $/Therm 0.6712 0.2668
G-42, G-52 $/Therm 0.6712 0.2465
G-43, G-53, T-1 $/Therm 0.6712 0.1803

Peak/Winter 2023-2024 Rates Revision 1 (Effective 1/1/24 through 4/30/24)

Berkshire Gas Company

Rate Class Billing Unit GAF LDAF
All Residential  $/Therm 0.7748 0.3595
G-41/G-51 $/Therm 0.7748 0.1611
G-42/G-52 $/Therm 0.7748 0.1098
G-43/G-53 $/Therm 0.7748 0.0871
T-54 $/Therm 0.7748 0.0182

 

Eversource Gas Company of Massachusetts (formerly Bay State Gas d/b/a Columbia Gas of Massachusetts)REVISED

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 0.5051 0.4339
Residential Heating R-3, R-4 $/Therm 0.6320 0.4339
G-40 $/Therm 0.6320 0.2838
G-41 $/Therm 0.6320 0.2019
G-42 $/Therm 0.6320 0.2032
G-43 $/Therm 0.6320 0.1808
G-50 $/Therm 0.5051 0.2838
G-51 $/Therm 0.5051 0.2019
G-52 $/Therm 0.5051 0.2032
G-53 $/Therm 0.5051 0.1808

 

Fitchburg Gas d/b/a Unitil

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 0.5889 0.7994
Residential Heating R-3, R-4 $/Therm 0.6276 0.7994
G-41 $/Therm 0.6276 0.5813
G-42 $/Therm 0.6276 0.3836
G-43 $/Therm 0.6276 0.3245
G-51 $/Therm 0.5889 0.5813
G-52 $/Therm 0.5889 0.3836
G-53 $/Therm 0.5889 0.3245

 

Liberty Utilities - Blackstone (formerly Blackstone Gas Company)REVISED

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.2125 0.1671
G-41, G-42, G-43 $/Therm 0.2125 0.0859
G-51, G-52, G-53 $/Therm 0.2125 0.0950

 

Liberty Utilities - North Attleboro/Fall RiverREVISED

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.3737 0.4574
G-41, G-42, G-43 $/Therm 0.3737 0.2743
G-51, G-52, G-53 $/Therm 0.3737 0.2307

 

National Grid - Boston Gas

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.8122 0.4746
G-41B/E, G-51B/E $/Therm 0.8122 0.2548
G-42B/E, G-52B/E $/Therm 0.8122 0.2373
G-43B/E, G-53B/E $/Therm 0.8122 0.2246
G-44B, G-54B $/Therm 0.4452 0.2008
G-44B, G-54B $/MDCQ Therms 5.7297  

 

National Grid - former Colonial Gas

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.8122 0.4077
G-41, G-51 $/Therm 0.8122 0.1869
G-42, G-52 $/Therm 0.8122 0.1793
G-43, G-53 $/Therm 0.8122 0.1530

 

NSTAR Gas Company d/b/a Eversource EnergyREVISED

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.6712 0.5033
G-41, G-51 $/Therm 0.6712 0.2668
G-42, G-52 $/Therm 0.6712 0.2465
G-43, G-53, T-1 $/Therm 0.6712 0.1803

Peak/Winter 2023-2024 Rates (Effective 11/1/23 through 12/31/23)

Berkshire Gas Company

Rate Class Billing Unit GAF LDAF
All Residential  $/Therm 0.7748 0.3595
G-41/G-51 $/Therm 0.7748 0.1611
G-42/G-52 $/Therm 0.7748 0.1098
G-43/G-53 $/Therm 0.7748 0.0871
T-54 $/Therm 0.7748 0.0182

 

Eversource Gas Company of Massachusetts (formerly Bay State Gas d/b/a Columbia Gas of Massachusetts)

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 0.5850 0.4339
Residential Heating R-3, R-4 $/Therm 0.7119 0.4339
G-40 $/Therm 0.7119 0.2838
G-41 $/Therm 0.7119 0.2019
G-42 $/Therm 0.7119 0.2032
G-43 $/Therm 0.7119 0.1808
G-50 $/Therm 0.5850 0.2838
G-51 $/Therm 0.5850 0.2019
G-52 $/Therm 0.5850 0.2032
G-53 $/Therm 0.5850 0.1808

 

Fitchburg Gas d/b/a Unitil

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 0.5889 0.7994
Residential Heating R-3, R-4 $/Therm 0.6276 0.7994
G-41 $/Therm 0.6276 0.5813
G-42 $/Therm 0.6276 0.3836
G-43 $/Therm 0.6276 0.3245
G-51 $/Therm 0.5889 0.5813
G-52 $/Therm 0.5889 0.3836
G-53 $/Therm 0.5889 0.3245

 

Liberty Utilities - Blackstone (formerly Blackstone Gas Company)

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.6258 0.1671
G-41, G-42, G-43 $/Therm 0.6258 0.0859
G-51, G-52, G-53 $/Therm 0.6258 0.0950

 

Liberty Utilities - North Attleboro/Fall River

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.5457 0.4574
G-41, G-42, G-43 $/Therm 0.5457 0.2743
G-51, G-52, G-53 $/Therm 0.5457 0.2307

 

National Grid - Boston Gas

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.8122 0.4746
G-41B/E, G-51B/E $/Therm 0.8122 0.2548
G-42B/E, G-52B/E $/Therm 0.8122 0.2373
G-43B/E, G-53B/E $/Therm 0.8122 0.2246
G-44B, G-54B $/Therm 0.4452 0.2008
G-44B, G-54B $/MDCQ Therms 5.7297  

 

National Grid - former Colonial Gas

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.8122 0.4077
G-41, G-51 $/Therm 0.8122 0.1869
G-42, G-52 $/Therm 0.8122 0.1793
G-43, G-53 $/Therm 0.8122 0.1530

 

NSTAR Gas Company d/b/a Eversource Energy

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.7680 0.5033
G-41, G-51 $/Therm 0.7680 0.2668
G-42, G-52 $/Therm 0.7680 0.2465
G-43, G-53, T-1 $/Therm 0.7680 0.1803

Off-Peak/Summer 2023 Rates Revision 4 (Effective 9/1/23 through 10/31/23)

Berkshire Gas Company

Rate Class Billing Unit GAF LDAF
All Residential  $/Therm 0.1489 0.4419
G-41/G-51 $/Therm 0.1489 0.2242
G-42/G-52 $/Therm 0.1489 0.1417
G-43/G-53 $/Therm 0.1489 0.0860
T-54 $/Therm 0.1489 0.0178

 

Eversource Gas Company of Massachusetts (formerly Bay State Gas d/b/a Columbia Gas of Massachusetts)

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 0.2303 0.4745
Residential Heating R-3, R-4 $/Therm 0.2535 0.4745
G-40 $/Therm 0.2535 0.2913
G-41 $/Therm 0.2535 0.2123
G-42 $/Therm 0.2535 0.1986
G-43 $/Therm 0.2535 0.1801
G-50 $/Therm 0.2303 0.2913
G-51 $/Therm 0.2303 0.2123
G-52 $/Therm 0.2303 0.1986
G-53 $/Therm 0.2303 0.1801

 

Fitchburg Gas d/b/a Unitil

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 0.3354 0.7165
Residential Heating R-3, R-4 $/Therm 0.3624 0.7165
G-41 $/Therm 0.3624 0.4943
G-42 $/Therm 0.3624 0.2999
G-43 $/Therm 0.3624 0.2369
G-51 $/Therm 0.3354 0.4943
G-52 $/Therm 0.3354 0.2999
G-53 $/Therm 0.3354 0.2369

 

Liberty Utilities - Blackstone (formerly Blackstone Gas Company)

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.4343 0.3985
G-41, G-42, G-43 $/Therm 0.4343 0.1896
G-51, G-52, G-53 $/Therm 0.4343 0.1209

 

Liberty Utilities - North Attleboro/Fall River

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.0636 0.6888
G-41, G-42, G-43 $/Therm 0.0636 0.3780
G-51, G-52, G-53 $/Therm 0.0636 0.2566

 

National Grid - Boston GasREVISED

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.1746 0.4796
G-41B/E, G-51B/E $/Therm 0.1746 0.2737
G-42B/E, G-52B/E $/Therm 0.1746 0.2526
G-43B/E, G-53B/E $/Therm 0.1746 0.2391
G-44B, G-54B $/Therm 0.0808 0.2111
G-44B, G-54B $/MDCQ Therms 1.0903  

 

National Grid - former Colonial GasREVISED

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.1746 0.3886
G-41, G-51 $/Therm 0.1746 0.1840
G-42, G-52 $/Therm 0.1746 0.1752
G-43, G-53 $/Therm 0.1746 0.1500

 

NSTAR Gas Company d/b/a Eversource EnergyREVISED

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.0233 0.5033
G-41, G-51 $/Therm 0.0233 0.2971
G-42, G-52 $/Therm 0.0233 0.2720
G-43, G-53, T-1 $/Therm 0.0233 0.2019

Off-Peak/Summer 2023 Rates Revision 3 (Effective 8/1/23 through 8/31/23)

Berkshire Gas Company

Rate Class Billing Unit GAF LDAF
All Residential  $/Therm 0.1489 0.4419
G-41/G-51 $/Therm 0.1489 0.2242
G-42/G-52 $/Therm 0.1489 0.1417
G-43/G-53 $/Therm 0.1489 0.0860
T-54 $/Therm 0.1489 0.0178

 

Eversource Gas Company of Massachusetts (formerly Bay State Gas d/b/a Columbia Gas of Massachusetts)

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 0.2303 0.4745
Residential Heating R-3, R-4 $/Therm 0.2535 0.4745
G-40 $/Therm 0.2535 0.2913
G-41 $/Therm 0.2535 0.2123
G-42 $/Therm 0.2535 0.1986
G-43 $/Therm 0.2535 0.1801
G-50 $/Therm 0.2303 0.2913
G-51 $/Therm 0.2303 0.2123
G-52 $/Therm 0.2303 0.1986
G-53 $/Therm 0.2303 0.1801

 

Fitchburg Gas d/b/a Unitil

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 0.3354 0.7165
Residential Heating R-3, R-4 $/Therm 0.3624 0.7165
G-41 $/Therm 0.3624 0.4943
G-42 $/Therm 0.3624 0.2999
G-43 $/Therm 0.3624 0.2369
G-51 $/Therm 0.3354 0.4943
G-52 $/Therm 0.3354 0.2999
G-53 $/Therm 0.3354 0.2369

 

Liberty Utilities - Blackstone (formerly Blackstone Gas Company)

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.4343 0.3985
G-41, G-42, G-43 $/Therm 0.4343 0.1896
G-51, G-52, G-53 $/Therm 0.4343 0.1209

 

Liberty Utilities - North Attleboro/Fall River

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.0636 0.6888
G-41, G-42, G-43 $/Therm 0.0636 0.3780
G-51, G-52, G-53 $/Therm 0.0636 0.2566

 

National Grid - Boston Gas

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.2273 0.4796
G-41B/E, G-51B/E $/Therm 0.2273 0.2737
G-42B/E, G-52B/E $/Therm 0.2273 0.2526
G-43B/E, G-53B/E $/Therm 0.2273 0.2391
G-44B, G-54B $/Therm 0.1254 0.2111
G-44B, G-54B $/MDCQ Therms 1.1319  

 

National Grid - former Colonial Gas

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.2273 0.3886
G-41, G-51 $/Therm 0.2273 0.1840
G-42, G-52 $/Therm 0.2273 0.1752
G-43, G-53 $/Therm 0.2273 0.1500

 

NSTAR Gas Company d/b/a Eversource EnergyREVISED

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.0889 0.5033
G-41, G-51 $/Therm 0.0889 0.2971
G-42, G-52 $/Therm 0.0889 0.2720
G-43, G-53, T-1 $/Therm 0.0889 0.2019

Off-Peak/Summer 2023 Rates Revision 2 (Effective 7/1/23 through 7/31/23)

Berkshire Gas CompanyREVISED

Rate Class Billing Unit GAF LDAF
All Residential  $/Therm 0.1489 0.4419
G-41/G-51 $/Therm 0.1489 0.2242
G-42/G-52 $/Therm 0.1489 0.1417
G-43/G-53 $/Therm 0.1489 0.0860
T-54 $/Therm 0.1489 0.0178

 

Eversource Gas Company of Massachusetts (formerly Bay State Gas d/b/a Columbia Gas of Massachusetts)

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 0.2303 0.4745
Residential Heating R-3, R-4 $/Therm 0.2535 0.4745
G-40 $/Therm 0.2535 0.2913
G-41 $/Therm 0.2535 0.2123
G-42 $/Therm 0.2535 0.1986
G-43 $/Therm 0.2535 0.1801
G-50 $/Therm 0.2303 0.2913
G-51 $/Therm 0.2303 0.2123
G-52 $/Therm 0.2303 0.1986
G-53 $/Therm 0.2303 0.1801

 

Fitchburg Gas d/b/a Unitil

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 0.3354 0.7165
Residential Heating R-3, R-4 $/Therm 0.3624 0.7165
G-41 $/Therm 0.3624 0.4943
G-42 $/Therm 0.3624 0.2999
G-43 $/Therm 0.3624 0.2369
G-51 $/Therm 0.3354 0.4943
G-52 $/Therm 0.3354 0.2999
G-53 $/Therm 0.3354 0.2369

 

Liberty Utilities - Blackstone (formerly Blackstone Gas Company)

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.4343 0.3985
G-41, G-42, G-43 $/Therm 0.4343 0.1896
G-51, G-52, G-53 $/Therm 0.4343 0.1209

 

Liberty Utilities - North Attleboro/Fall River

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.0636 0.6888
G-41, G-42, G-43 $/Therm 0.0636 0.3780
G-51, G-52, G-53 $/Therm 0.0636 0.2566

 

National Grid - Boston GasREVISED

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.2273 0.4796
G-41B/E, G-51B/E $/Therm 0.2273 0.2737
G-42B/E, G-52B/E $/Therm 0.2273 0.2526
G-43B/E, G-53B/E $/Therm 0.2273 0.2391
G-44B, G-54B $/Therm 0.1254 0.2111
G-44B, G-54B $/MDCQ Therms 1.1319  

 

National Grid - former Colonial GasREVISED

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.2273 0.3886
G-41, G-51 $/Therm 0.2273 0.1840
G-42, G-52 $/Therm 0.2273 0.1752
G-43, G-53 $/Therm 0.2273 0.1500

 

NSTAR Gas Company d/b/a Eversource Energy

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.1474 0.5033
G-41, G-51 $/Therm 0.1474 0.2971
G-42, G-52 $/Therm 0.1474 0.2720
G-43, G-53, T-1 $/Therm 0.1474 0.2019

Off-Peak/Summer 2023 Rates Revision 1 (Effective 6/1/23 through 6/30/23)

Berkshire Gas Company

Rate Class Billing Unit GAF LDAF
All Residential  $/Therm 0.3614 0.4419
G-41/G-51 $/Therm 0.3614 0.2242
G-42/G-52 $/Therm 0.3614 0.1417
G-43/G-53 $/Therm 0.3614 0.0860
T-54 $/Therm 0.3614 0.0178

 

Eversource Gas Company of Massachusetts (formerly Bay State Gas d/b/a Columbia Gas of Massachusetts)REVISED

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 0.2303 0.4745
Residential Heating R-3, R-4 $/Therm 0.2535 0.4745
G-40 $/Therm 0.2535 0.2913
G-41 $/Therm 0.2535 0.2123
G-42 $/Therm 0.2535 0.1986
G-43 $/Therm 0.2535 0.1801
G-50 $/Therm 0.2303 0.2913
G-51 $/Therm 0.2303 0.2123
G-52 $/Therm 0.2303 0.1986
G-53 $/Therm 0.2303 0.1801

 

Fitchburg Gas d/b/a Unitil

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 0.3354 0.7165
Residential Heating R-3, R-4 $/Therm 0.3624 0.7165
G-41 $/Therm 0.3624 0.4943
G-42 $/Therm 0.3624 0.2999
G-43 $/Therm 0.3624 0.2369
G-51 $/Therm 0.3354 0.4943
G-52 $/Therm 0.3354 0.2999
G-53 $/Therm 0.3354 0.2369

 

Liberty Utilities - Blackstone (formerly Blackstone Gas Company)

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.4343 0.3985
G-41, G-42, G-43 $/Therm 0.4343 0.1896
G-51, G-52, G-53 $/Therm 0.4343 0.1209

 

Liberty Utilities - North Attleboro/Fall River

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.0636 0.6888
G-41, G-42, G-43 $/Therm 0.0636 0.3780
G-51, G-52, G-53 $/Therm 0.0636 0.2566

 

National Grid - Boston GasREVISED

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.2839 0.4796
G-41B/E, G-51B/E $/Therm 0.2839 0.2737
G-42B/E, G-52B/E $/Therm 0.2839 0.2526
G-43B/E, G-53B/E $/Therm 0.2839 0.2391
G-44B, G-54B $/Therm 0.1759 0.2111
G-44B, G-54B $/MDCQ Therms 1.1557  

 

National Grid - former Colonial GasREVISED

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.2839 0.3886
G-41, G-51 $/Therm 0.2839 0.1840
G-42, G-52 $/Therm 0.2839 0.1752
G-43, G-53 $/Therm 0.2839 0.1500

 

NSTAR Gas Company d/b/a Eversource EnergyREVISED

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.1474 0.5033
G-41, G-51 $/Therm 0.1474 0.2971
G-42, G-52 $/Therm 0.1474 0.2720
G-43, G-53, T-1 $/Therm 0.1474 0.2019

Off-Peak/Summer 2023 Rates (Effective 5/1/23 through 5/31/23)

Berkshire Gas Company

Rate Class Billing Unit GAF LDAF
All Residential  $/Therm 0.3614 0.4419
G-41/G-51 $/Therm 0.3614 0.2242
G-42/G-52 $/Therm 0.3614 0.1417
G-43/G-53 $/Therm 0.3614 0.0860
T-54 $/Therm 0.3614 0.0178

 

Eversource Gas Company of Massachusetts (formerly Bay State Gas d/b/a Columbia Gas of Massachusetts)

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 0.2492 0.4760
Residential Heating R-3, R-4 $/Therm 0.2725 0.4760
G-40 $/Therm 0.2725 0.2932
G-41 $/Therm 0.2725 0.2134
G-42 $/Therm 0.2725 0.1995
G-43 $/Therm 0.2725 0.1808
G-50 $/Therm 0.2492 0.2932
G-51 $/Therm 0.2492 0.2134
G-52 $/Therm 0.2492 0.1995
G-53 $/Therm 0.2492 0.1808

 

Fitchburg Gas d/b/a Unitil

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 0.3354 0.7165
Residential Heating R-3, R-4 $/Therm 0.3624 0.7165
G-41 $/Therm 0.3624 0.4943
G-42 $/Therm 0.3624 0.2999
G-43 $/Therm 0.3624 0.2369
G-51 $/Therm 0.3354 0.4943
G-52 $/Therm 0.3354 0.2999
G-53 $/Therm 0.3354 0.2369

 

Liberty Utilities - Blackstone (formerly Blackstone Gas Company)

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.4343 0.3985
G-41, G-42, G-43 $/Therm 0.4343 0.1896
G-51, G-52, G-53 $/Therm 0.4343 0.1209

 

Liberty Utilities - North Attleboro/Fall River

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.0636 0.6888
G-41, G-42, G-43 $/Therm 0.0636 0.3780
G-51, G-52, G-53 $/Therm 0.0636 0.2566

 

National Grid - Boston Gas

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.4217 0.4796
G-41B/E, G-51B/E $/Therm 0.4217 0.2737
G-42B/E, G-52B/E $/Therm 0.4217 0.2526
G-43B/E, G-53B/E $/Therm 0.4217 0.2391
G-44B, G-54B $/Therm 0.2905 0.2111
G-44B, G-54B $/MDCQ Therms 1.2451  

 

National Grid - former Colonial Gas

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.4217 0.3886
G-41, G-51 $/Therm 0.4217 0.1840
G-42, G-52 $/Therm 0.4217 0.1752
G-43, G-53 $/Therm 0.4217 0.1500

 

NSTAR Gas Company d/b/a Eversource Energy

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.1831 0.5033
G-41, G-51 $/Therm 0.1831 0.2971
G-42, G-52 $/Therm 0.1831 0.2720
G-43, G-53, T-1 $/Therm 0.1831 0.2019

Peak/Winter 2022-2023 Rates Revision 3 (Effective 3/1/23 through 4/30/23)

Berkshire Gas Company

Rate Class Billing Unit GAF LDAF
All Residential  $/Therm 0.8272 0.3258
G-41/G-51 $/Therm 0.8272 0.1356
G-42/G-52 $/Therm 0.8272 0.1071
G-43/G-53 $/Therm 0.8272 0.0854
T-54 $/Therm 0.8272 0.0265

 

Eversource Gas Company of MassachusettsREVISED (formerly Bay State Gas d/b/a Columbia Gas of Massachusetts)

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 0.4302 0.4760
Residential Heating R-3, R-4 $/Therm 0.5569 0.4760
G-40 $/Therm 0.5569 0.2932
G-41 $/Therm 0.5569 0.2134
G-42 $/Therm 0.5569 0.1995
G-43 $/Therm 0.5569 0.1808
G-50 $/Therm 0.4302 0.2932
G-51 $/Therm 0.4302 0.2134
G-52 $/Therm 0.4302 0.1995
G-53 $/Therm 0.4302 0.1808

 

Fitchburg Gas d/b/a Unitil

Rate Class Billing Unit GAF LDAF1
Residential Non-Heating R-1, R-2 $/Therm 0.9643 0.6471
Residential Heating R-3, R-4 $/Therm 1.0412 0.6471
G-41 $/Therm 1.0412 0.4353
G-42 $/Therm 1.0412 0.2630
G-43 $/Therm 1.0412 0.2058
G-51 $/Therm 0.9643 0.4353
G-52 $/Therm 0.9643 0.2630
G-53 $/Therm 0.9643 0.2058

1Effective March 1, 2023, Unitil's LDAF for all rate classes decreased due to Department approval of the company’s lower Gas System Enhancement Reconciliation Adjustment Factor in D.P.U. 22-GREC-01.

 

Liberty Utilities - Blackstone (formerly Blackstone Gas Company)

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.4919 0.3985
G-41, G-42, G-43 $/Therm 0.4919 0.1896
G-51, G-52, G-53 $/Therm 0.4919 0.1209

 

Liberty Utilities - North Attleboro/Fall River

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.8534 0.6447
G-41, G-42, G-43 $/Therm 0.8534 0.3463
G-51, G-52, G-53 $/Therm 0.8534 0.2474

 

National Grid - Boston GasREVISED

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.6897 0.4360
G-41B/E, G-51B/E $/Therm 0.6897 0.2308
G-42B/E, G-52B/E $/Therm 0.6897 0.2149
G-43B/E, G-53B/E $/Therm 0.6897 0.2038
G-44B, G-54B $/Therm 0.3665 0.1857
G-44B, G-54B $/MDCQ Therms 5.2779  

 

National Grid - former Colonial GasREVISED

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.6897 0.3743
G-41, G-51 $/Therm 0.6897 0.1731
G-42, G-52 $/Therm 0.6897 0.1647
G-43, G-53 $/Therm 0.6897 0.1452

 

NSTAR Gas Company d/b/a Eversource Energy

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.7779 0.4566
G-41, G-51 $/Therm 0.7779 0.2561
G-42, G-52 $/Therm 0.7779 0.2340
G-43, G-53, T-1 $/Therm 0.7779 0.1819

Peak/Winter 2022-2023 Rates Revision 2 (Effective 2/1/23 through 2/28/23)

Berkshire Gas CompanyREVISED

Rate Class Billing Unit GAF LDAF1
All Residential  $/Therm 0.8272 0.3258
G-41/G-51 $/Therm 0.8272 0.1356
G-42/G-52 $/Therm 0.8272 0.1071
G-43/G-53 $/Therm 0.8272 0.0854
T-54 $/Therm 0.8272 0.0265

1Berkshire Gas Company's LDAF for all rate classes increased on January 1, 2023 due to a Distribution Rate Settlement Agreement with the Attorney General, approved in Berkshire Gas Company, D.P.U. 22-20 (January 4, 2023). 

 

Eversource Gas Company of Massachusetts (formerly Bay State Gas d/b/a Columbia Gas of Massachusetts)

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 0.8545 0.4760
Residential Heating R-3, R-4 $/Therm 0.9812 0.4760
G-40 $/Therm 0.9812 0.2932
G-41 $/Therm 0.9812 0.2134
G-42 $/Therm 0.9812 0.1995
G-43 $/Therm 0.9812 0.1808
G-50 $/Therm 0.8545 0.2932
G-51 $/Therm 0.8545 0.2134
G-52 $/Therm 0.8545 0.1995
G-53 $/Therm 0.8545 0.1808

 

Fitchburg Gas d/b/a UnitilREVISED

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 0.9643 0.6695
Residential Heating R-3, R-4 $/Therm 1.0412 0.6695
G-41 $/Therm 1.0412 0.4616
G-42 $/Therm 1.0412 0.2770
G-43 $/Therm 1.0412 0.2171
G-51 $/Therm 0.9643 0.4616
G-52 $/Therm 0.9643 0.2770
G-53 $/Therm 0.9643 0.2171

Liberty Utilities - Blackstone (formerly Blackstone Gas Company)REVISED

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.4919 0.3985
G-41, G-42, G-43 $/Therm 0.4919 0.1896
G-51, G-52, G-53 $/Therm 0.4919 0.1209

 

Liberty Utilities - North Attleboro/Fall RiverREVISED

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.8534 0.6447
G-41, G-42, G-43 $/Therm 0.8534 0.3463
G-51, G-52, G-53 $/Therm 0.8534 0.2474

National Grid - Boston GasREVISED

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.8904 0.4360
G-41B/E, G-51B/E $/Therm 0.8904 0.2308
G-42B/E, G-52B/E $/Therm 0.8904 0.2149
G-43B/E, G-53B/E $/Therm 0.8904 0.2038
G-44B, G-54B $/Therm 0.5082 0.1857
G-44B, G-54B $/MDCQ Therms 6.1275  

National Grid - former Colonial GasREVISED

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.8904 0.3743
G-41, G-51 $/Therm 0.8904 0.1731
G-42, G-52 $/Therm 0.8904 0.1647
G-43, G-53 $/Therm 0.8904 0.1452

NSTAR Gas Company d/b/a Eversource EnergyREVISED

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.7779 0.4566
G-41, G-51 $/Therm 0.7779 0.2561
G-42, G-52 $/Therm 0.7779 0.2340
G-43, G-53, T-1 $/Therm 0.7779 0.1819

Peak/Winter 2022-2023 Rates Revision 1 (Effective 12/1/22 through 1/31/23)

Berkshire Gas Company

Rate Class Billing Unit GAF LDAF
All Residential  $/Therm 1.0894 0.3214
G-41/G-51 $/Therm 1.0894 0.1432
G-42/G-52 $/Therm 1.0894 0.1182
G-43/G-53 $/Therm 1.0894 0.0963
T-54 $/Therm 1.0894 0.0290

Eversource Gas Company of Massachusetts (formerly Bay State Gas d/b/a Columbia Gas of Massachusetts)REVISED

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 0.8545 0.4760
Residential Heating R-3, R-4 $/Therm 0.9812 0.4760
G-40 $/Therm 0.9812 0.2932
G-41 $/Therm 0.9812 0.2134
G-42 $/Therm 0.9812 0.1995
G-43 $/Therm 0.9812 0.1808
G-50 $/Therm 0.8545 0.2932
G-51 $/Therm 0.8545 0.2134
G-52 $/Therm 0.8545 0.1995
G-53 $/Therm 0.8545 0.1808

 

Fitchburg Gas d/b/a Unitil

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 1.0892 0.6695
Residential Heating R-3, R-4 $/Therm 1.1661 0.6695
G-41 $/Therm 1.1661 0.4616
G-42 $/Therm 1.1661 0.2770
G-43 $/Therm 1.1661 0.2171
G-51 $/Therm 1.0892 0.4616
G-52 $/Therm 1.0892 0.2770
G-53 $/Therm 1.0892 0.2171

Liberty Utilities - Blackstone (formerly Blackstone Gas Company)

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 1.7197 0.3985
G-41, G-42, G-43 $/Therm 1.7197 0.1896
G-51, G-52, G-53 $/Therm 1.7197 0.1209

 

Liberty Utilities - North Attleboro/Fall River

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.9664 0.6447
G-41, G-42, G-43 $/Therm 0.9664 0.3463
G-51, G-52, G-53 $/Therm 0.9664 0.2474

National Grid - Boston GasREVISED

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.9870 0.4360
G-41B/E, G-51B/E $/Therm 0.9870 0.2308
G-42B/E, G-52B/E $/Therm 0.9870 0.2149
G-43B/E, G-53B/E $/Therm 0.9870 0.2038
G-44B, G-54B $/Therm 0.5545 0.1857
G-44B, G-54B $/MDCQ Therms 6.9474  

National Grid - former Colonial GasREVISED

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.9870 0.3743
G-41, G-51 $/Therm 0.9870 0.1731
G-42, G-52 $/Therm 0.9870 0.1647
G-43, G-53 $/Therm 0.9870 0.1452

NSTAR Gas Company d/b/a Eversource EnergyREVISED

Rate Class Billing Unit GAF LDAF1
All Residential $/Therm 1.0378 0.4566
G-41, G-51 $/Therm 1.0378 0.2561
G-42, G-52 $/Therm 1.0378 0.2340
G-43, G-53, T-1 $/Therm 1.0378 0.1819

 

1NSTAR Gas Company's LDAF for all rate classes decreased on January 1, 2023 due to the Department's order in NSTAR Gas Company, D.P.U. 22-145 (December 30, 2022).

Peak/Winter 2022-2023 Rates (Effective 11/1/22 through 11/30/22)

Berkshire Gas Company

Rate Class Billing Unit GAF LDAF
All Residential  $/Therm 1.0894 0.3214
G-41/G-51 $/Therm 1.0894 0.1432
G-42/G-52 $/Therm 1.0894 0.1182
G-43/G-53 $/Therm 1.0894 0.0963
T-54 $/Therm 1.0894 0.0290

Eversource Gas Company of Massachusetts (formerly Bay State Gas d/b/a Columbia Gas of Massachusetts)

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 0.9203 0.4760
Residential Heating R-3, R-4 $/Therm 1.0470 0.4760
G-40 $/Therm 1.0470 0.2932
G-41 $/Therm 1.0470 0.2134
G-42 $/Therm 1.0470 0.1995
G-43 $/Therm 1.0470 0.1808
G-50 $/Therm 0.9203 0.2932
G-51 $/Therm 0.9203 0.2134
G-52 $/Therm 0.9203 0.1995
G-53 $/Therm 0.9203 0.1808

 

Fitchburg Gas d/b/a Unitil

Rate Class Billing Unit GAF LDAF
Residential Non-Heating R-1, R-2 $/Therm 1.0892 0.6695
Residential Heating R-3, R-4 $/Therm 1.1661 0.6695
G-41 $/Therm 1.1661 0.4616
G-42 $/Therm 1.1661 0.2770
G-43 $/Therm 1.1661 0.2171
G-51 $/Therm 1.0892 0.4616
G-52 $/Therm 1.0892 0.2770
G-53 $/Therm 1.0892 0.2171

Liberty Utilities - Blackstone (formerly Blackstone Gas Company)

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 1.7197 0.3985
G-41, G-42, G-43 $/Therm 1.7197 0.1896
G-51, G-52, G-53 $/Therm 1.7197 0.1209

 

Liberty Utilities - North Attleboro/Fall River

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 0.9664 0.6447
G-41, G-42, G-43 $/Therm 0.9664 0.3463
G-51, G-52, G-53 $/Therm 0.9664 0.2474

National Grid - Boston Gas

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 1.0498 0.4360
G-41B/E, G-51B/E $/Therm 1.0498 0.2308
G-42B/E, G-52B/E $/Therm 1.0498 0.2149
G-43B/E, G-53B/E $/Therm 1.0498 0.2038
G-44B, G-54B $/Therm 0.6183 0.1857
G-44B, G-54B $/MDCQ Therms 6.9285  

National Grid - former Colonial Gas

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 1.0498 0.3743
G-41, G-51 $/Therm 1.0498 0.1731
G-42, G-52 $/Therm 1.0498 0.1647
G-43, G-53 $/Therm 1.0498 0.1452

NSTAR Gas Company d/b/a Eversource Energy

Rate Class Billing Unit GAF LDAF
All Residential $/Therm 1.1101 0.4799
G-41, G-51 $/Therm 1.1101 0.2668
G-42, G-52 $/Therm 1.1101 0.2399
G-43, G-53, T-1 $/Therm 1.1101 0.1864

 


Contact   for Cost of Gas Adjustment Factor Rates and Information

Online

For questions related to your gas bill, visit the DPU Consumer Division page 

Address

Department of Public Utilities
One South Station, 3rd Floor, Boston, MA 02110
Last updated: June 30, 2023

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