The hardest part of filing yourself is finding comparable sales. So we built a free tool for it. Type an address into our comps page and you'll see three recent sales of similar homes nearby. It doesn't cover condos or co-ops yet.
A list of sales is only useful if you know how it was made. Here are the rules, in the order the page applies them.
How the page picks the sales
1. Same town and same school district. Every sale comes from the same town and school district as your house. Homes a few blocks away can sit in a different district, and we leave those out.
2. Sold in the last two years, at a normal sale. The county asks what your home was worth on a set date each year. We only use sales within two years before that date. We also skip sales the county marks as not a normal market sale, like a transfer between family members.
3. Similar size and age. We start strict: within 20% of your home's living space and within 15 years of its age. If that doesn't find enough sales, we loosen it one step, then one more, and stop there.
4. Close by. We start with sales within about a mile and a quarter. If there aren't enough, we widen to about two and a half miles, then three. We never go past three miles.
5. Closest match first. Of the sales left, we rank them by how close they are to your home on living space, then age, then lot size. Living space counts the most. The page shows the top three, with each sale's date, price, size, lot and year built, plus the middle price of the three.
The same rules choose the sales we attach when we file for a client. What you see on the page is what we'd use.
The comps page isn't an appraisal or a professional opinion of value.
How to use them on your own filing
- Check your own record first. Look up your address on the county's Land Record Viewer. Make sure the living space, bedrooms, bathrooms and lot match your house. A wrong number there throws off every comparison.
- Review each sale. Look it up online. If one sale is a renovated house on a busy corner and yours isn't, drop it. You can add sales you find yourself.
- Pick your number. The county's form asks what your home would have sold for on its value date. The middle sale is a fair place to start. Then move up or down for the ways your house differs, like a smaller lot or a roof that needs work.
- File during the window. The Nassau County Assessment Review Commission takes filings for the 2028/29 tax year from January 4 to March 1, 2027. Filing is free, and you can do it online. Attach the sales you used.