FAQ · 4 min read

Does an Unfinished Basement Count as Square Footage?

No -- an unfinished basement does not count as square footage (GLA) for appraisal purposes. But it does get reported, and it can still affect your home's appraised value. Here is how it works.

The short answer

An unfinished basement is excluded from Gross Living Area (GLA) under ANSI Z765-2021 -- the standard used by licensed appraisers for residential homes. Two reasons:

It is below grade. Basements are typically below the exterior grade line, which automatically excludes them from GLA regardless of finish level.
It is unfinished. Even in rare cases where a basement could be considered above grade (unusual hillside construction), it would still need to be finished to count as GLA.

The MLS listing square footage and county assessor records sometimes include basement area -- which is why listed square footage can look much larger than the appraised GLA. The appraisal follows ANSI Z765; those other sources often do not.

How appraisers report unfinished basement area

On a standard URAR appraisal form, basements are broken out in a dedicated section separate from the above-grade room count and GLA. The appraiser reports:

Total basement area (square feet)
Finished portion of basement (square feet)
Features: walkout, below-grade windows, utility area, etc.

An unfinished basement shows up in the total basement area but contributes zero to the finished area figure. Both above-grade and below-grade areas are used when selecting and adjusting comparable sales.

Does an unfinished basement add any value?

Yes -- though much less than above-grade GLA or finished basement area. Unfinished basement space typically contributes $5-15 per square foot toward appraised value in most markets, compared to $50-150+ for above-grade GLA. The actual adjustment depends heavily on local market data and what comparable sales show.

A large, clean unfinished basement with good ceiling height, proper egress, and utility access is more valuable than a small, low-ceiling, utility-only space -- even if neither shows up in the GLA figure. Appraisers account for this in their comparable adjustments.

Finishing a basement: does it change the GLA?

Finishing a basement makes it finished below-grade area -- which has higher contributory value than unfinished. But it still does not become GLA. Below-grade space cannot become GLA regardless of finish level, because it is below grade.

The exception would be if the space were truly at or above exterior grade on all sides -- but that is structurally rare and requires careful evaluation of the grade line around the entire perimeter, not just one wall.

What about listing square footage that includes the basement?

This is common and causes confusion for buyers. Agents sometimes list total square footage (above-grade + finished basement combined) because it makes the home look larger. County assessor records may also include basement area.

When an appraiser measures the home, the GLA will only reflect above-grade space. If a home was listed at 2,400 sq ft (1,600 above grade + 800 finished basement) and the appraisal shows 1,600 sq ft of GLA, the appraisal is correct -- not wrong.

Buyers should always ask: is that square footage above-grade only, or does it include the basement?