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

For South Carolina, 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 South Carolina does not allow bonus depreciation. Addition or subtraction is required for the difference in depreciation expense claimed for federal purposes and the amount allowed for state purposes, recorded from its source on 2026-08-15.

- **State:** South Carolina _(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:** South Carolina does not allow bonus depreciation. Addition or subtraction is required for the difference in depreciation expense claimed for federal purposes and the amount allowed for state purposes. _(verified: appears in the quote below)_
- **Has income tax:** yes _(verified: appears in the quote below)_

## What the source says

> State Follows Bonus Depreciation-TCJA of 2017 : No South Carolina does not conform to the Tax Cuts and Jobs Act provision that provides a 100% first-year deduction for the adjusted basis that is allowed for qualified property acquired and placed in service after September 27, 2017, and before January 1, 2023. South Carolina does not allow bonus depreciation. Addition or subtraction is required for the difference in depreciation expense claimed for federal purposes and the amount allowed for state purposes. State Follows IRC § 179-TCJA of 2017 : Yes South Carolina 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.

## 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 **South Carolina does not allow bonus depreciation. Addition or subtraction is required for the difference in depreciation expense claimed for federal purposes and the amount allowed for state purposes.**, as of 2026-08-15.

> State Follows Bonus Depreciation-TCJA of 2017 : No South Carolina does not conform to the Tax Cuts and Jobs Act provision that provides a 100% first-year deduction for the adjusted basis that is allowed for qualified property acquired and placed in service after September 27, 2017, and before January 1, 2023. South Carolina does not allow bonus depreciation. Addition or subtraction is required for the difference in depreciation expense claimed for federal purposes and the amount allowed for state purposes. State Follows IRC § 179-TCJA of 2017 : Yes South Carolina 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.

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 **South Carolina does not conform to bonus depreciation**, as of 2026-08-15.

> South Carolina | 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/).