South Carolina Act 388: How the 4% Primary vs 6% Non-Primary Tax Ratio Hits Your Escrow — Palmetto Passage
Updated October 2026
A South Carolina home's current tax bill may be a poor forecast of your first mortgage payment. Legal-residence approval, ownership changes and local millage can produce a bill very different from the seller's. The crucial distinction is 4% primary-residence assessment treatment versus 6% non-primary treatment, not a 4% or 6% tax rate.
Understand what Act 388 changes
Qualifying owner-occupied legal residences use a 4% assessment ratio and receive a 100% exemption from school operating taxes. Second homes, investor properties and other nonqualifying residences generally use the 6% ratio without that exemption.
| Assessment component | Approved legal residence | Non-primary residence |
|---|---|---|
| Assessment ratio | 4% | Generally 6% |
| School operating taxes | Fully exempt | Generally included |
| School debt and other applicable levies | May still apply | May still apply |
| County approval | Legal-residence application required | No primary-residence benefit |
For a $350,000 assessed market value, the ratio produces a $14,000 assessment base at 4%, compared with $21,000 at 6%. Those figures are not annual tax bills. Applicable millage, exemptions and charges determine the actual amount.
Because school operating taxes also change, the non-primary bill can often be roughly 2.5 to 3.5 times the approved legal-residence bill. The exact difference depends on the taxing district.
Apply and budget before escrow surprises arrive
Do not assume the seller's legal-residence classification automatically transfers to you. Ask the county assessor which application, ownership evidence and residency documents are required, and confirm the applicable filing deadline.
If the loan initially escrows taxes using 6% treatment, approval of 4% treatment may later reduce the projection. Conversely, a lender using an unrealistically low seller bill can leave an escrow shortage after the actual bill arrives.
Send the updated county information to the servicer and ask how it will affect the next escrow analysis. A county approval does not guarantee an immediate payment change or instant refund.
The South Carolina Department of Revenue provides state property-tax resources. The Consumer Financial Protection Bureau explains mortgage costs and escrow considerations.
Stress-test the payment before making an offer
Request estimates for both approved legal-residence treatment and the initial treatment likely to appear on the tax account. Keep insurance separate so the tax savings do not conceal higher coastal premiums.
Run both scenarios through the monthly payment calculator. If the home is near the coast, also review the wind and flood escrow guide before setting your maximum payment.
Editorial Methodology & Primary Sources
Verification date: Not recorded; check the primary source and lender timestamp before relying on an estimate.
Rate comparisons use participating lender feeds, not a whole-market survey or guaranteed offers. Freddie Mac PMMS is a market benchmark, not a personalized quote. Calculator models rely on published regulatory formulas and disclosed assumptions rather than fabricated first-person loan testing.
Monthly principal and interest use the amortization formula P × r / (1 − (1 + r)−n), where r is the monthly note rate and n is the number of payments; at zero interest use P / n. PITI adds monthly property taxes and homeowners insurance; PMI is separate. APR includes applicable finance charges under Regulation Z and is not the note rate used for payments. Compare lender Loan Estimates for actual APR and fees.
- Consumer Financial Protection Bureau (CFPB) — Loan Estimates, APR and borrower disclosures; Regulation Z.
- U.S. Department of Housing and Urban Development (HUD / FHA) — FHA program guidance.
- U.S. Department of Veterans Affairs (VA) — VA loan eligibility and benefits.
- Freddie Mac Primary Mortgage Market Survey (PMMS) — published rate benchmarks.
- U.S. Census state tax collections — state property tax benchmarks; confirm parcel-specific assessments and exemptions with the state revenue department and local assessor.
- SC Housing — state housing finance and property tax authority.
- South Carolina Department of Revenue — state housing finance and property tax authority.
The payment snapshot uses illustrative annual taxes of 1% of home price, $1,200 insurance and 0.5% PMI below 20% down, not verified local quotes. Other calculators disclose their inputs and assumptions. Published guidance and lender feeds may change independently; confirm current program rules, taxes and offers before a decision.