Key takeaways
- Returns are due on or before the 15th day of the month after the period, and monthly is the default schedule.
- The general rate is 5.5%, prepared food and liquor in licensed establishments are 8%, and lodging is 9%.
- Maine's time-computation statute moves a report due on a weekend or legal holiday to the next business day.
- A late return costs the greater of $25 or 10% of the tax due, and late payment adds 1% a month up to 25%.
- Ask clients for sales split by tax rate, because one blended total cannot be reported correctly.
The 15th, and which schedule the client files on
Under 36 M.R.S. section 1951-A, every retailer files a return on or before the 15th day of each month covering the preceding calendar month. Monthly is the statutory default. The State Tax Assessor may permit a different schedule, so a small seller may be assigned quarterly or annual filing. I could not read Maine Revenue Services' own page for the thresholds that drive the assignment, because the agency site blocked my requests, so treat any threshold you see on a third-party site as unverified.
The practical rule is to read the frequency off the client's account in the Maine Tax Portal, not from memory or from last year's file. For a new client, pull the registration confirmation and record the schedule and the first period in your calendar the day you onboard them.
Tax is legally due when the sale is made. Section 1952 lets the assessor postpone payment, but not past the date the sales are required to be reported. The 15th is therefore the last day for both the return and the money.
Due dates for monthly filers, November 2026 through February 2027
Maine's general time-computation statute, 1 M.R.S. section 71(13), says a required report due on a Saturday, Sunday or legal holiday is due by close of business on the next day that is not one of those. Apply it to the calendar below, and confirm the date the portal displays for each period.
October 2026 sales: the 15th of November falls on a Sunday, so the working due date is Monday, November 16, 2026. November 2026 sales: Tuesday, December 15, 2026. December 2026 sales, also the last period for a calendar-year annual filer: Friday, January 15, 2027.
January 2027 sales: February 15, 2027 is a Monday, and that is Presidents Day. I did not confirm the holiday on a statute page, so do not plan to the 16th. Put the Friday before on your internal calendar and treat the 16th as a possible bonus only after the portal confirms it. A late payment is the client's penalty, so the early date costs nothing.
A client may ask for more time. The statute lets the assessor extend a deadline by up to 30 days for good cause. That is a request made to the assessor with a reason, not an automatic right, so do not tell a client one exists before the request is approved.
Rates: the return is split by what was sold
Under 36 M.R.S. section 1811, the rate is 5.5% on tangible personal property and taxable services. Prepared food is 8%, and so is liquor sold in licensed establishments. Lodging is 9%, and short-term vehicle rentals under one year are 10%. Adult-use cannabis was 10% through the end of 2025 and the statute makes it 14% for later sales, so a tax year 2026 return uses 14% for it.
That split is what trips up mixed clients. A restaurant that also sells retail goods, such as bottled sauces or merchandise, has sales at 8% and sales at 5.5% in the same month. An inn with a gift shop has 9% and 5.5%. A bookkeeper who books one gross sales number and multiplies by a single rate will misstate the return in both directions.
Worked example: a restaurant reports $62,000 of prepared food and liquor sales and $4,000 of retail sales for the month. Tax is $62,000 times 8%, which is $4,960 (prepared food), plus $4,000 times 5.5%, which is $220 (retail), for $5,180 in total. A flat 8% on $66,000 gives $5,280 and an over-collection of $100 that the client either owes to customers or keeps wrongly.
Penalties and what a missed 15th costs
Under 36 M.R.S. section 187-B, failing to file when more than $25 is due carries a penalty of $25 or 10% of the tax due, whichever is greater, if the return is filed within 60 days after a formal demand. If it is still not filed 60 days after the demand, the penalty becomes $25 or 25%, whichever is greater.
Failing to pay the tax shown on a return adds 1% of the unpaid tax for each month or fraction of a month, capped at 25% of the unpaid tax. Interest is separate, and the statute says interest may not accrue on the penalty itself. On the restaurant above, a $5,180 return filed but unpaid for two months and a day draws a 3% penalty, or $155.40, before interest.
A zero return is worth filing. I could not confirm on a primary source whether Maine requires one for a seller with no sales, so file one anyway for any registered client, because a missing return is what generates the demand.
Remote sellers, marketplaces and resale certificates
Under 36 M.R.S. section 1754-B, a seller with no physical presence must register once gross sales delivered into Maine exceed $100,000 in the previous or current calendar year. The statute applies the same $100,000 figure to marketplace facilitators, counting sales they facilitate for others. Count all deliveries into Maine, taxable or not, because the test is gross sales.
For an e-commerce client, run a ship-to-state report by month and note the month Maine passes the line. Send this: "Please export orders by ship-to state for the year to date, including marketplace orders, so I can check whether Maine registration is required." The nexus guide linked below covers the wider process.
Resale certificates matter because exempt sales only help if documented. Maine issues a resale certificate to applicants expecting annual gross sales of $3,000 or more, and each November 1 it reviews returns and renews certificates for retailers with $3,000 or more in the prior 12 months, effective for 5 calendar years. When a client sells for resale, keep the buyer's certificate with the invoice.
What to collect each period
Send the request on the 1st and set your own deadline for the 8th, which leaves time before the 15th. Ask for a point-of-sale or storefront sales report by rate category, for the whole calendar month, with the tax collected line. Ask for the processor and marketplace payout reports separately, so that marketplace-collected sales can be removed.
Ask for any exempt-sale invoices with the buyer's resale certificate attached, any credit memos or refunds that reduce taxable sales, and the filing confirmation from last period. Decision rule: if sales tax collected on the report differs from the liability account by more than a few dollars, hold the return and ask the client what was sold at the wrong rate.
Usual can run this as a recurring monthly request with a due date and automatic reminders, and each period's documents are stored under the client. The return itself is still filed by you in the state portal.