Portland’s rent stabilization ordinance caps how much an apartment owner can raise rent on most covered units each year, and for calendar year 2027 that cap is 2.6%. On top of the city ordinance, owners must follow Maine’s statewide landlord-tenant statutes, and where the two differ, Portland’s stricter local rule usually controls.
Where Portland’s rent rules come from
Portland voters approved rent control in the November 2020 referendum, and the city began implementing it in 2021. Voters amended it in November 2022: the annual increase formula was reduced, application fees were banned, security deposits were capped at one month’s rent, and notice periods were lengthened to 90 days. Two 2023 ballot questions that would have loosened the ordinance, one to reset rent at voluntary turnover and one to exempt owners of nine or fewer units, were each rejected by roughly two-thirds of voters.
The practical result is a set of rules that has been stable since 2022. The city’s rent control and tenant protection FAQ is the most useful single reference for owners.
How the annual increase is calculated
Each covered unit has a Base Rent, generally the rent in effect on June 1, 2020, or the first rent charged for a unit created later. From there, rent may rise once every 12 months by the Allowable Increase Percentage, which equals 70% of the change in the consumer price index for the Greater Boston metro area. The city publishes the figure by September 1 for the following calendar year.
- 2024: 2.0%
- 2025: 2.5%
- 2026: 2.2%
- 2027: 2.6%, as reported by the Portland Press Herald when the city set it this September
A few mechanisms add flexibility. Unused increases can be banked and applied later. When a tenant leaves voluntarily, the owner may add 5% to the Base Rent for the new tenancy. Larger increases tied to capital improvements or a fair rate of return require approval from the city’s Rent Board. In every case, no covered unit’s rent may rise more than 10% in a year. A change of ownership does not reset Base Rent, which matters to anyone buying or selling a building here.
Which buildings are exempt
The ordinance reaches most long-term rentals in the city, but the FAQ lists several exemptions:
- Owner-occupied buildings with two to four units
- Units with public subsidies such as Section 8, plus housing authority units
- Accessory dwelling units
- Hospital, religious and extended-care facilities
- College and Portland Public Schools dormitories
A five-unit building where the owner lives on site does not qualify for the owner-occupied exemption, and the city’s FAQ lists no general exemption for newer construction. Owners should confirm a building’s status before setting rents or underwriting an acquisition.
Notice periods and tenant protections
Portland’s notice rules are longer than the state baseline. A rent increase requires at least 90 days’ written notice that states the reasons for the increase and the banked-rent balance. Maine law, under 14 M.R.S. §6015, otherwise requires 45 days’ notice, or 75 days for an increase of 10% or more. A no-cause termination in Portland requires 90 days’ notice versus 30 days under state law, and an owner who gives a shorter notice must pay the tenant one or two months’ rent depending on the timing. For-cause terminations, such as for unpaid rent, still follow the 7-day timeline.
Other local requirements include:
- No application fees of any kind, and security deposits capped at one month’s rent (state law allows up to two)
- A city Housing Rights Document given to tenants at lease signing, with the signed acknowledgment kept for three years
- No discrimination based on source of income or rental subsidy
Registration and statewide rules
Every long-term rental unit in Portland must be registered with the city each year. For the 2025–2026 rental year, the fee is $55 per unit, with discounts of up to $20 per unit for features such as sprinklers, monitored alarms or a no-smoking lease. Registrations expire December 31. A newly rented unit must be registered within 14 days, and a new owner has 30 days after a transfer. Late fees reach $200 per unit after 45 days, so registration is worth putting on the calendar for any building changing hands.
Statewide rules still apply alongside the ordinance. Deposits must be returned within 30 days under a written lease, or 21 days for a tenancy at will. Under 14 M.R.S. §6030-H, landlords anywhere in Maine may charge applicants only the actual cost of one screening report. Rent cannot be raised while a unit is in violation of the warranty of habitability.
Practical takeaways for building owners
Rent control changes how a Portland building’s income should be read. A rent roll here is more than a list of current rents. It reflects each unit’s Base Rent, any banked increases and the 2.6% ceiling for 2027. When below-market units turn over voluntarily, the owner gets only a 5% reset, so rents in a long-held building can lag the open market for years.
For owners weighing their options, a few steps help:
- Reconcile every unit’s current rent to its documented Base Rent and increase history
- Keep notices, Housing Rights Document acknowledgments and registrations organized, since a buyer’s due diligence will ask for them
- Model income using the allowable increase rather than market rent growth
Owners comparing rules across states can use our rent control and property tax guide by state, and the Maine market overview covers conditions beyond Portland. For owners thinking about selling an apartment building in Portland, that page explains how we evaluate rent-stabilized properties.
