Property Tax Reassessments: What Homeowners Need to Know

Sep 16

If you own property in Charleston County, you’ve likely received a reassessment notice in the mail (sent out August 20). These notices reveal what the county believes your property is worth for tax purposes — and for many homeowners, they bring more questions than answers.

The good news: reassessments happen only once every five years, and their primary purpose is to redistribute the tax burden fairly. The not-so-good news: figuring out what that means for your own tax bill can feel like learning a new language.

Here’s a clear breakdown of what’s happening, and what it means for you.

What is a reassessment?

Reassessments are required by state law to ensure that tax values reflect current market conditions. They don’t automatically raise more tax revenue for the county — they simply update the property values used to calculate each owner’s share of the overall tax base.

How does the county calculate assessed value?

The market value determined by county assessors is multiplied by a ratio based on property use:

Owner-occupied homes: 4%
Other properties (rentals, second homes, commercial): 6%

Example:

A $500,000 primary residence → assessed at $20,000
A $500,000 rental property → assessed at $30,000

This assessed value is then plugged into the local tax formula.

What about my property tax bill?

Assessed values work like taxable income. Local governments and school districts apply millage rates (tax rates) to the assessed value to calculate your bill.

By law, local governments must adjust those rates after reassessment so that total revenue doesn’t automatically increase. However, it’s not uncommon for millage rates (and thus tax bills) to rise in reassessment years, leaving homeowners wondering whether the change was caused by reassessment or a tax hike.

My assessment went up — does that mean my taxes will too?

Not necessarily. It depends on how your property’s value changed compared to the county average:

If your property value increased more than average, your share of the tax burden may rise.
If your property value increased less than average, your taxes may stay the same or even decrease.

In other words, reassessment reshuffles the tax deck — some will pay more, some less.

What about the 15% cap?

South Carolina’s Act 388 (2007) limits how much a property’s taxable value can increase during reassessment to 15% — but only if the property hasn’t changed ownership.

When a property changes hands, it’s reassessed at full market value and then capped for future reassessments until another ownership transfer occurs.

Important note: the cap applies to assessed value, not the final tax bill. That’s why long-time owners often pay lower taxes than new buyers of similar homes.

Is this what my home is worth right now?

No. Reassessment values are based on sales data from two years prior to the reassessment year. For the current reassessment cycle, Charleston County is using values as of December 31, 2023. The last cycle in 2020 was based on 2018 values.

So, while your notice shows what the county believes your home was worth at the end of 2023, it doesn’t reflect today’s market value.

Key Takeaways for Homeowners