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When Property Taxes Are Due in Greater Portland, and What Late Costs You

Published August 15, 2026 · 10 min read

There is no state property tax due date in Maine. There is no state interest rate on late property taxes either, whatever the town clerk on the phone implies when she says "that is what the state charges." What exists is a ceiling, posted once a year by the Treasurer of State, and twelve separate votes underneath it.

The spread that produces is larger than almost anyone expects. Pay your Cumberland tax bill sixty days late and the town charges you 4 percent a year. Do the same thing eight miles away in Gorham and the published number is 8 percent. Same county, same statute, double the rate.

And if you are reading this in August 2026 and checking your own town's page, there is a decent chance the numbers you are looking at belong to a fiscal year that ended on June 30.

The rate is a vote, and the ceiling moved this year

36 M.R.S. section 505(4) is the operative sentence. It says the rate of interest must be specified in the vote, and that the maximum rate must be established by the Treasurer of State and may not exceed the prime rate published in the Wall Street Journal on the first business day of the calendar year, rounded up to the next whole percent, plus 3 percentage points.

Two things follow that most homeowners have never been told.

First, the ceiling is keyed to the calendar year in which your town commits its tax roll, not to the fiscal year printed on your bill. A town that commits in September 2026 is bound by the 2026 number even though its bill says 2026-27.

Second, the number changed. The Treasurer of State posts the table publicly, and it reads 7.00 percent for taxable year 2026, down from 7.50 percent for 2025 and 8.50 percent for 2024. Treasurer Joe Perry announced the cut on January 9, 2026.

That single fact explains most of the table below. Every Greater Portland town that has already committed for this fiscal year has moved to 7 percent. Every town still showing 7.5 percent has not committed yet, and is showing you last year's rate.

There is no floor. The Maine Municipal Association is explicit that a municipality may set a lower rate than the maximum if it wishes, including a rate of 0 percent, and that if a municipality fails to set any rate at all, no interest accrues on late payments. Cumberland's 4 percent is not an oversight. It is a choice its Town Council made and could have made lower.

Due dates and interest, town by town

Every row below was read on the municipality's own website on August 15, 2026. The middle column is the one to read first.

Nine of the twelve had not published a 2026-27 due date on August 15. That is not negligence, it is the calendar: commitment across this region runs from early July to early October, and a town cannot vote a due date before it votes a tax rate. Portland says so on its own Treasury page, in as many words: the mill rate has not been set, and due dates have not yet been determined, with bills expected in the first couple of weeks of September 2026. Cape Elizabeth carries a notice dated August 10, 2026 saying its balances will be updated later this month.

What the towns do not do is label the stale rows. Portland's property tax page still leads with "payments are due on October 17, 2025 and March 20, 2026," which is true of a fiscal year that is over. Nothing on the page says so.

Three things in that table that are not what they look like

Westbrook bills quarterly. It is the only one of the twelve that does, and it is a real difference in cash flow rather than a formatting quirk. Four payments of a quarter each, on August 17 and November 16, 2026 and February 15 and May 17, 2027, with interest starting the day after each one. Westbrook is also the only town in the group that publishes its interest accrual start dates as dates rather than leaving you to infer "the day after."

Windham's own website disagrees with itself. The Assessor page carries the current figures from the August 11, 2026 commitment: due October 1, 2026 and April 1, 2027, interest 7 percent. The Tax Collection page still shows October 1, 2025, April 1, 2026, and 7.5 percent. A resident who lands on the second page gets a superseded rate with nothing marking it as old. If you are relying on the number, call the Tax Collection Office at 207-892-2511.

Gorham's 8 percent is the one figure here we could not settle. The town's assessing page shows an 8 percent overdue interest rate alongside a commitment date of September 26, 2025. A September 2025 commitment falls in taxable year 2025, and the Treasurer's ceiling for 2025 was 7.50 percent. We are not calling that a violation, because two ordinary explanations fit and we could not rule either out: the page may simply be carrying forward an older figure, and 8 percent was comfortably lawful for a 2024 commitment when the ceiling was 8.50 percent. We could not retrieve the Town Council order that set the rate. If you owe Gorham money, the finance office at 207-222-1610 can tell you which commitment year the 8 percent attaches to, and it is worth asking.

The refund rule nobody mentions

If you overpay, or win an abatement after paying, the town owes you interest back. Section 506-A caps that rate at the town's own delinquent rate and floors it at that rate minus 4 percentage points. A town at 7.5 percent may lawfully pay you back anywhere from 3.5 to 7.5 percent. A town at 4 percent may lawfully pay you 0.

So the low-interest town is not simply the generous one. Cumberland's 4 percent is the friendliest rate in the region if you are late and the least useful in the region if the town has held your money by mistake. If the town sets no refund rate at all, section 506-A defaults it to the full delinquent rate, which is the outcome that favors you.

Prepayment runs on a third number entirely. Section 506 lets a municipality accept prepayment of taxes not yet committed and pay interest on it at a rate not exceeding 8 percent per year, and it is explicit that no municipality is obliged to pay anything.

What is actually worth doing about this

Partial payments are the underused lever. Cumberland accepts payment of any amount toward taxes that have not foreclosed, and applies it to interest first and then principal. South Portland states plainly that you may prepay the balance or pay in installments as frequently as you like, so long as the full amount arrives by the due date. Windham says it encourages partial payments, with one exclusion that matters: not during the tax lien process, when current-year taxes must be paid in full and by cash or bank check only. Scarborough is the outlier in the other direction and says it no longer accepts payments scheduled for a future date.

Maine also allows something none of the twelve advertised on the pages we read on August 15, 2026: section 505(5) permits a town to vote a discount of up to 10 percent for taxpayers who pay early. It is legal here. It is simply not a thing local towns currently do, which is worth knowing before you assume paying early buys you anything.

One last mechanical point, and it is the one that catches people who try to negotiate. Under section 505 the rate and the due dates are fixed by the vote taken before commitment, and neither can be altered after taxes have been committed for the year. There is no discretion at the counter. What the counter can do is set up a payment arrangement, which several of these towns will, and which stops nothing accruing but does keep you out of the lien and foreclosure clock.

If your objection is to the size of the bill rather than the timing, the interest rate is the wrong lever anyway. That is an abatement question, and it has its own 185-day deadline counted from the same commitment date this article keeps pointing at. And if you are comparing towns before buying, the mill rate on its own will mislead you, which is the subject of what you actually pay by town.

FAQ

What is the maximum interest rate a Maine town can charge on late property taxes in 2026?

7.00 percent. The Treasurer of State posts the maximum each January under 36 M.R.S. section 505(4), and the 2026 figure is a reduction from 7.50 percent for taxable year 2025 and 8.50 percent for 2024. The ceiling applies to taxes committed during that calendar year, so it follows your town's commitment date rather than the fiscal year on your bill.

Do all Maine towns charge the same interest on late property taxes?

No, and the spread is wide. Among twelve Greater Portland towns read on August 15, 2026, published rates ran from 4 percent in Cumberland to 8 percent in Gorham, with most at 7.5 percent and the towns that have already committed for 2026-27 at 7 percent. The rate is set by a vote of the municipal legislative body, and the Maine Municipal Association confirms a town may set any rate below the ceiling, including zero.

When are property taxes due in Portland, Maine?

Portland had not set its 2026-27 due dates as of August 15, 2026. Its Treasury page states that the mill rate has not been set and due dates have not yet been determined, with bills expected in the first couple of weeks of September 2026. Its 2025-26 installments were due October 17, 2025 and March 20, 2026 at 7.5 percent interest.

Does Maine law require property taxes to be paid in two installments?

No. 36 M.R.S. section 505(2) leaves it entirely to the municipality, granting authority over "the date or dates when property taxes shall become due and payable." That permissive plural is why Westbrook bills quarterly, the other eleven towns in this region bill semiannually, and first-half due dates across those eleven span mid-September to mid-November.

Does my town pay me interest if I overpay my property taxes?

Yes, under 36 M.R.S. section 506-A, but at a rate the town sets. It may not exceed the town's own delinquent rate and may not be less than that rate minus 4 percentage points. A town charging 7.5 percent may refund at anywhere from 3.5 to 7.5 percent. If the town never set a refund rate, the statute defaults it to the full delinquent rate.

Can I negotiate the interest on my late Maine property tax bill?

Not the rate. Section 505 fixes both the rate and the due dates in the vote taken before commitment, and neither may be changed afterward for that tax year. Several towns here will arrange a payment plan, and Cumberland, South Portland and Windham each publish partial-payment terms, but interest keeps running on whatever is unpaid.

What happens if my Maine town never votes an interest rate?

No interest accrues. The Maine Municipal Association states that interest does not accrue on unpaid taxes unless the municipal legislative body establishes both the rate and the dates from which it runs, and that this must be done annually. All twelve towns in this comparison had a published rate on August 15, 2026.

Every town figure here was read on the municipality's own website on August 15, 2026, and the maximum rates come from the Treasurer of State's published table. Nine of the twelve had not committed for 2026-27 that day, so their rows show a closed fiscal year. We will re-read all twelve after the autumn commitment season and replace them.