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In Morris Plains Borough, a property tax appeal mostly comes down to one number: your assessment divided by 70.46 percent. If your home would really sell for less than that, the board's required to lower your assessment. Here's how to work out your number, the 2027 deadline, and the risk most people don't know about.
Now New Jersey decides most appeals with arithmetic, under a rule people call Chapter 123. The state works out how Morris Plains Borough's assessments compare with what homes there really sell for, and for 2027 appeals that official ratio's 61.27 percent. That's down from 68.10 percent last year, which usually means home prices in town rose faster than assessments did. Basically, the board leaves your assessment alone as long as your own ratio falls within 15 percent of the town's either way, which here means between 52.08 and 70.46 percent. Here's how that works out on a home assessed at $400,000.
| What it means | Example |
|---|---|
| What the assessor is really saying the home's worth: the assessment divided by 61.27 percent | $652,848 |
| The board has to cut the assessment if the home's really worth less than this: the assessment divided by 70.46 percent | $567,694 |
| The board has to raise it if the home's really worth more than this: the assessment divided by 52.08 percent | $768,057 |
So the one question that really matters is whether your home would sell for less than your own assessment divided by 70.46 percent. You don't have to prove the assessor made a mistake, which surprises a lot of people. If your home's true value is under that line, the board's required to bring you down to 61.27 percent of it.
But it works the other way too. If your home's actually worth more than your assessment divided by 52.08 percent, the board has to raise your assessment, even though you're the one who appealed. So it's worth checking which side of both lines you're on before you file.
Appeals in Morris County are due April 1, 2027. It's May 1 instead in a town that's put a revaluation or reassessment into effect that year.
Now the petition has to be received by the county board by that date, so a postmark doesn't count. Copies also have to go to the town's assessor and its clerk, and missing one's enough to get an appeal dismissed. Also, your property taxes need to be paid up through the first quarter, or the board can dismiss it without a hearing.
Fortunately filing's cheap. It costs between $5 and $150, depending on your assessment: $5 under $150,000, $25 up to $500,000, $100 up to $1,000,000, and $150 above that.
Well, honestly, most people shouldn't. But in New Jersey a lot more people could win than actually try. When we ran the Chapter 123 test against recent sales in 302 towns, about 1 in 5 homes came out above the line, mostly because ordinary sale prices vary more than the legal range allows. Yet only about 1 in 267 homeowners filed a residential appeal in 2025.
So it's worth five minutes to check. Our free check looks up your home in the state's own records, applies Morris Plains Borough's official ratio, shows you your line, and it'll show you what homes assessed like yours have actually sold for. If you're inside the range, it'll tell you pretty plainly not to bother.
And there's more on how the arithmetic plays out across the state in our New Jersey odds article.
Morris Plains Borough's ratio comes from the New Jersey Division of Taxation's Table of Equalized Valuations for 2026, promulgated October 1, 2026, and that's the table county boards apply to 2027 appeals. Towns can challenge it in the Tax Court within 45 days, so a few ratios could still get revised, though most won't. The range rule is N.J.S.A. 54:51A-6, and the filing fees are N.J.S.A. 54:3-21.3. The deadlines, the copies, the payment rule and the Monmouth exceptions come from the Division's guide to tax appeal hearings and the Monmouth County Board of Taxation's handbook.
And the 1 in 5 figure's our own measurement of 73,771 sales in 302 towns in 2025 and 2026. The 9,524 residential appeals filed in 2025 is the Division's figure as it's been reported in the press, and we haven't read it in the original.
If you spot an error, please write to hello@propertytaxbuddy.com and we'll correct it and say what changed.