# Massachusetts — State conformity to federal Section 179 and bonus depreciation rules

For Massachusetts, section 179 conformity is conforms; state section 179 cap is federal limit applies; state section 179 phase-out is federal phase-out applies; bonus depreciation conformity is decouples — requires add-back; add-back rule is Massachusetts specifically decoupled from the federal bonus depreciation provisions under IRC § 168(k), recorded from its source on 2026-08-15.

- **State:** Massachusetts _(verified: appears in the quote below)_
- **Section 179 conformity:** conforms _(verified: appears in the quote below)_
- **State Section 179 cap:** federal limit applies
- **State Section 179 phase-out:** federal phase-out applies
- **Bonus depreciation conformity:** decouples — requires add-back
- **Add-back rule:** Massachusetts specifically decoupled from the federal bonus depreciation provisions under IRC § 168(k) _(verified: appears in the quote below)_
- **IRC conformity date:** rolling conformity
- **Has income tax:** yes _(verified: appears in the quote below)_
- **Statute or guidance citation:** IRC § 168(k) _(verified: appears in the quote below)_

## What the source says

> State Follows Bonus Depreciation-TCJA of 2017 : No Massachusetts does not conform to the Tax Cuts and Jobs Act provision that provides a 100% first-year deduction for the adjusted basis is allowed for qualified property acquired and placed in service after September 27, 2017, and before January 1, 2023. Massachusetts specifically decoupled from the federal bonus depreciation provisions under IRC § 168(k). State Follows IRC § 179-TCJA of 2017 : Yes Massachusetts conforms to the Tax Cuts and Jobs Act provision that increases the maximum amount a taxpayer may expense under IRC Section 179 to $1 million, increases the phase-out threshold amount to $2.5 million, and provides for indexing for inflation. Massachusetts adopts the IRC as amended and in effect for the taxable year.

## Sources disagree

More than one authority states this, and they do not state the same
thing. Both are reproduced with the source each came from.

### Add-back rule

accountants.intuit.com says add-back rule is **Massachusetts specifically decoupled from the federal bonus depreciation provisions under IRC § 168(k)**, as of 2026-08-15.

> State Follows Bonus Depreciation-TCJA of 2017 : No Massachusetts does not conform to the Tax Cuts and Jobs Act provision that provides a 100% first-year deduction for the adjusted basis is allowed for qualified property acquired and placed in service after September 27, 2017, and before January 1, 2023. Massachusetts specifically decoupled from the federal bonus depreciation provisions under IRC § 168(k). State Follows IRC § 179-TCJA of 2017 : Yes Massachusetts conforms to the Tax Cuts and Jobs Act provision that increases the maximum amount a taxpayer may expense under IRC Section 179 to $1 million, increases the phase-out threshold amount to $2.5 million, and provides for indexing for inflation. Massachusetts adopts the IRC as amended and in effect for the taxable year.

Source: https://accountants.intuit.com/support/en-us/help-article/asset-depreciation/state-conformity-special-depreciation-allowance/L27kRyetJ_US_en_US

crosslinktax.com says add-back rule is **Massachusetts does not conform to bonus depreciation**, as of 2026-08-15.

> Massachusetts | No | Yes |

Source: https://www.crosslinktax.com/customer-resources/tax-resource-center/tax-updates/state-compliance-with-federal-bonus-depreciation-and-section-179-expensing-2025/


## Source

- https://accountants.intuit.com/support/en-us/help-article/asset-depreciation/state-conformity-special-depreciation-allowance/L27kRyetJ_US_en_US
- https://www.crosslinktax.com/customer-resources/tax-resource-center/tax-updates/state-compliance-with-federal-bonus-depreciation-and-section-179-expensing-2025/

Last verified: 2026-08-15. Review by: 2027-08-15.
Part of [State conformity to federal Section 179 and bonus depreciation rules](https://referencesource.org/state-section-179-bonus-depreciation-conformity/).