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Updated 2025 Tax Year

Union County
Property Tax Guide

Everything you need to know about property taxes in Union County, SC. Rates, due dates, exemptions, and how it affects your monthly payment.

10 Official Sources
8 min read
Quick Facts
Tax Rate
2.97 mills base rate + special district assessments (varies by location)
Exemptions
4+ Available
Section 1

How Property Tax Works

Union County, South Carolina operates on a property tax system that funds essential county services including schools, emergency services, roads, and local government operations. The county assesses property taxes based on a percentage of the property's fair market value, with residential properties assessed at 4% of fair market value for owner-occupied homes and 6% for non-owner occupied properties.

Property tax rates in Union County vary significantly by location due to multiple special taxing districts within the county. The base county rate for FY 2025-2026 is approximately 2.97 mills per $100 of assessed value, but residents may also pay additional assessments for special districts such as Island City Sanitation, 4H/Extension services, and Vector Control. Total effective tax rates typically range from 0.59% to over 1% of assessed value depending on your specific location and applicable special districts.

Property owners should note that tax rates and special district assessments can change annually based on budget requirements and local needs. The county provides detailed tax information through the Union County Assessor's Office, and property owners are encouraged to verify their specific tax obligations and available credits through official county channels.

Section 2

What Makes Up Your Tax Bill

ComponentRate (per $100 assessed)Description
Base County Levy$2.9668Core county services, administration, public safety
Island City Sanitation$0.5814Waste management services (specific district only)
4H/Extension Services$0.1619Agricultural extension and youth programs
Vector Control$0.0239Mosquito and pest control services

Rates shown are for FY 2025-2026 levy year. Special district rates apply only to properties within those specific districts. Your total tax rate depends on which special districts serve your property location. Contact the Union County Assessor's Office to determine which special districts apply to your specific property address.

Note: These rates are applied to assessed value, not market value. Owner-occupied residential properties are assessed at 4% of fair market value, while non-owner occupied properties are assessed at 6% of fair market value.

Section 3

When Are Property Taxes Due?

For the 2025/2026 tax year in Union County, property taxes are due in two installments:

Pro tip: If you pay through mortgage escrow, your lender splits these payments across your monthly mortgage. If you pay directly, set calendar reminders to avoid late penalties.
Section 4

Supplemental Tax Bills

Supplemental taxes in Union County are additional property taxes triggered by changes in property ownership, new construction, or property improvements that occur after the annual assessment date. These taxes cover the period from when the change occurred until the end of the current tax year.

Supplemental taxes are calculated by determining the difference between the old assessed value and the new assessed value, then applying the current tax rate to this difference. The tax is prorated based on the number of months remaining in the tax year. For example, if you purchase a home in January that was previously assessed at a lower value, you'll receive a supplemental tax bill for the difference between the previous owner's assessment and the current market-based assessment.

Common triggers for supplemental taxes include: property sales that result in reassessment, completion of new construction or major renovations, changes in property use (such as converting from agricultural to residential), and corrections to previous assessments. Property owners typically receive supplemental tax bills within 30-60 days of the triggering event, and these taxes follow the same payment schedule and penalty structure as regular property taxes.

Example Calculation

Example 1: $300,000 Home (Owner-Occupied)

  • Market Value: $300,000
  • Assessment Rate: 4% (owner-occupied)
  • Assessed Value: $12,000
  • Less: Homestead Credit: $2,000 (on $50,000 exemption × 4%)
  • Net Taxable Value: $10,000
  • Tax Rate: $2.97 per $100 (base county rate)
  • Annual Tax: $297 | Monthly: $25

Example 2: $600,000 Home (Owner-Occupied)

  • Market Value: $600,000
  • Assessment Rate: 4% (owner-occupied)
  • Assessed Value: $24,000
  • Less: Homestead Credit: $2,000 (on $50,000 exemption × 4%)
  • Net Taxable Value: $22,000
  • Tax Rate: $2.97 per $100 (base county rate)
  • Annual Tax: $653 | Monthly: $54

Example 3: $1,000,000 Home (Owner-Occupied)

  • Market Value: $1,000,000
  • Assessment Rate: 4% (owner-occupied)
  • Assessed Value: $40,000
  • Less: Homestead Credit: $2,000 (on $50,000 exemption × 4%)
  • Net Taxable Value: $38,000
  • Tax Rate: $2.97 per $100 (base county rate)
  • Annual Tax: $1,129 | Monthly: $94

Note: These examples use base county rates only. Additional special district taxes may apply. All tax credits require application and approval. Rates shown are for FY 2025-2026.

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Section 5

Escrow & Property Taxes

Most mortgage lenders in Union County require property tax escrow accounts for borrowers with less than 20% down payment or upon borrower request. Lenders collect 1/12 of your estimated annual property tax bill with each monthly mortgage payment, holding these funds in an escrow account to pay your taxes when due.

Property taxes in Union County are due September 1st, with a grace period until January 5th to avoid interest charges. Lenders typically pay your taxes in early fall to ensure timely payment and avoid penalties. Your lender will receive tax bills directly from Union County and handle payment on your behalf. You should receive an annual escrow statement from your lender showing deposits, payments, and account balances.

Property owners with escrow accounts should monitor their tax assessments and notify their lender of any significant changes, such as successful assessment appeals or newly qualified tax credits. Changes in your property tax bill may require escrow payment adjustments. If your taxes increase significantly, your lender may require a one-time escrow shortage payment in addition to higher monthly payments. Conversely, if taxes decrease, you may receive a refund or see reduced monthly escrow payments.

How HonestCasa Helps
  • Understand whether your escrow is set correctly
  • See how rising taxes will change your monthly payment
  • Plan ahead instead of being surprised by "shortage" letters
Section 6

Frequently Asked Questions

Q: When are property taxes due for the current fiscal year? A: Property taxes for FY 2025-2026 are due September 1, 2025. You can pay without interest until January 5, 2026. After January 5th, interest and penalties begin accruing.

Q: What homestead tax credit is available and how do I apply? A: Union County offers a homestead tax credit that exempts $50,000 of fair market value (reducing assessed value by $2,000 for owner-occupied homes). This credit requires application through the Union County Assessor's Office and is NOT automatic. You must own and occupy the home as your primary residence.

Q: Are there tax credits available for seniors or disabled persons? A: Yes, South Carolina provides additional tax credits for seniors over 65 and disabled individuals, including totally disabled firefighters and law enforcement officers. These credits require application with documentation such as Workers' Compensation orders or disability certifications. Contact the Union County Assessor's Office for specific application requirements and deadlines.

Q: How often are properties reassessed in Union County? A: Union County conducts property reassessments periodically, typically every 5-6 years countywide, though significant improvements or sales may trigger individual reassessments. The county uses the assessment ratio of 4% for owner-occupied residential properties and 6% for other properties.

Q: How do I appeal my property assessment? A: Property owners can appeal assessments by filing with the Union County Board of Assessment Appeals within 90 days of receiving their assessment notice. Appeals require evidence supporting your claimed value, such as recent appraisals or comparable sales data.

Q: What happens if I pay my property taxes late? A: Interest begins accruing after January 5th at rates set by state law. Properties with delinquent taxes may be included in the annual delinquent tax sale, typically held in September following the tax year. The Sheriff's Office maintains delinquent tax listings through April 15th.

Q: Can I pay my property taxes online? A: Contact the Union County Treasurer's Office for current online payment options and accepted methods. Many South Carolina counties offer online payment systems for property taxes.

Q: Why do my taxes vary from my neighbor's even though our homes are similar? A: Tax amounts can vary due to different assessed values, eligibility for tax credits (which require application), and location within different special taxing districts. Special districts like Island City Sanitation add additional taxes that only apply to properties within those district boundaries.

Q: Do I need to reapply for tax credits each year? A: Most tax credits require only initial application, but some may require periodic renewal or notification of changes in eligibility. Contact the Union County Assessor's Office to confirm renewal requirements for your specific credits.

Q: What documentation do I need to apply for the homestead credit? A: You typically need a recorded deed showing ownership, proof of residency (such as voter registration or driver's license), and confirmation of the 4% owner-occupied assessment ratio from the county assessor's office. Contact the assessor for a complete list of required documents.

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