Short-term rental (Airbnb) rules in Portland, Maine
Only if the home is your primary residence. On the mainland, a single-family home can be a short-term rental (under 30 days) only if it is owner-occupied or tenant-occupied with the owner's permission. Every unit must be registered with Permitting & Inspections each year; the first owner-occupied unit costs $100. Non-owner-occupied units are capped citywide, ADUs count as non-owner-occupied (newly built ADUs are exempt from the cap for 5 years), and new tenant-occupied registrations stopped in 2026.
| What counts as a short-term rental | Renting a unit, in whole or in part, for less than 30 days [1] |
| Registration | Required for every rental unit, renewed by January 1 each year [2] |
| Single-family homes | Only if owner-occupied, tenant-occupied with owner permission, or on Peaks/Outer Islands [8] |
| Annual fee, first owner-occupied unit | $100 (rises to $250, $500, $1,000, $2,000 for 2nd-5th units) [5] |
| Annual fee, first non-owner-occupied mainland unit | $200 (rises to $4,000 for a 5th unit) [6] |
| Guest occupancy limit | 2 guests per bedroom plus 2 more [7] |
| Cap on non-owner-occupied mainland STRs | 1.5% of registered long-term rental units (400 in 2025) [9] |
| ADUs | Counted as non-owner-occupied; ADUs registered within 5 years of their certificate of occupancy are excluded from the citywide cap [12] |
| Max STR units per person or entity | 5 [10] |
| Registration number | Must appear in the unit and in every listing [4] |
| Penalty for false registration information | $1,000 [11] |
Registration and fees
A short-term rental is any rental of a unit, whole or in part, for less than 30 days [1]. Every rental unit must be registered by January 1 each year, and a new unit must be registered within 14 days of entering the market [2]. Owner-occupants must file a notarized primary-residence affidavit and show ID plus proof of the homestead exemption (or a recent tax return). The city then issues a registration number, which must be shown in the unit and in every ad, and booking platforms must include it in listings [4]. Fees are cumulative per registrant: $100 for the first owner-occupied unit [5] and $200 for the first non-owner-occupied mainland unit, rising steeply for each additional unit [6]. Late registrations add $50 to $200 per unit.
Who can operate
On the mainland, a single-family home can be an STR only if it is owner-occupied, or tenant-occupied with the owner's permission [8]. "Primary residence" means where you live more than half the year and list for tax and ID purposes. An accessory dwelling unit is not treated as owner-occupied, even on your own lot [3], but an ADU that got its certificate of occupancy within 5 years before registration doesn't count toward the citywide cap [12]. Since January 1, 2026, no new tenant-occupied STRs are allowed. Owners may register up to five rooms or spaces within their own primary residence, and no one may register more than five STR units in total [10].
Caps and building limits
Non-owner-occupied mainland STRs are capped at 1.5% of registered long-term rentals (400 in 2025) [9]. They are allocated first-come, first-registered with a waitlist, and registrations can't be transferred. Units registered as of December 31, 2025 are grandfathered. Multi-unit buildings have their own limits, for example one STR in a 2- or 3-unit building. Peaks Island has a separate cap of 40 non-owner-occupied STRs.
Guests and enforcement
Guests are limited to 2 per bedroom plus 2 more [7]. You must answer city inquiries within 48 hours. Giving false registration information carries a $1,000 penalty [11], and a property declared a disorderly house can lose its registration for 12 months. Condo units also need the association's written attestation that STRs are allowed.
See how Portland compares with 8+ other Maine towns on short-term rentals (airbnb / vrbo) →
Next steps
- Confirm the home is your primary residence (or that the unit qualifies under the multi-unit or island rules); a whole home you don't live in on the mainland can't be registered.
- Apply for short-term rental registration with Permitting & Inspections (portlandmaine.gov/short-term-rental-registration) and bring a notarized primary-residence affidavit, your ID, and proof of the homestead exemption or a recent tax return.
- If you're in a condo, get the association's signed attestation that STRs are allowed, plus a copy of its governing documents.
- Pay the annual fee, then put the city registration number in the unit and in every Airbnb or VRBO listing; renew by January 1 each year.
- Separately register with Maine Revenue Services for lodging tax if required.
Common questions
- Can I Airbnb my house in Portland, Maine?
- Only if it's your primary residence. On the mainland, a single-family home can be a short-term rental only if it's owner-occupied or tenant-occupied with the owner's permission. Every unit must be registered each year.
- How much does it cost to register a short-term rental in Portland, Maine?
- The first owner-occupied unit costs $100 per year. The first non-owner-occupied mainland unit costs $200, and fees rise for additional units.
- Is there a cap on short-term rentals in Portland, Maine?
- Yes, for non-owner-occupied mainland units: 1.5% of registered long-term rentals (400 in 2025). Peaks Island has a separate cap of 40. ADUs count as non-owner-occupied.
- How many guests are allowed in a short-term rental in Portland, Maine?
- Guests are limited to 2 per bedroom plus 2 more.
- Do I need to list my registration number on Airbnb in Portland, Maine?
- Yes. The city registration number must appear in the unit and in every listing.
Maine state rules for short-term rentals
No statewide STR license. Maine has no state registration or permit for Airbnb/VRBO hosts. State law instead lets each town regulate short-term rentals (30-A M.R.S. §4364-C(2), passed in 2022). Check your town's rules.
Lodging tax (Maine Revenue Services):
- Rentals of living quarters are taxed at 9%, still the rate in 2026.
- Booking platforms such as Airbnb and VRBO must register with the state and collect the tax on bookings made through them.
- If you rent a single unit for fewer than 15 days a year, you generally aren't a "retailer" and don't need to register.
- If you rent 15 days or more in a year, you must register with Maine Revenue Services and collect tax on any bookings you take directly.
- A stay of 28+ days in a row is tax-exempt only in certain cases, such as when the unit is the guest's primary residence.
No state lodging license for vacation rentals. Maine's lodging-license law leaves out "vacation rentals," meaning homes rented to people with a permanent home elsewhere. B&Bs, inns and hotels do need a license.
ADUs: Starting July 1, 2027, towns can't require ADU owners to live on the property. State guidance says towns can still regulate STRs, for example by requiring registration or banning STRs in ADUs.
What the ordinance says
- Sec. 6-150.1 (Short Term Rental), Buildings and Building Regulations (Chapter 6) – incl. short-term rental registration, p. 39
Short Term Rental is the letting of a rental unit, in whole or in part, for less than thirty (30) days.
- Sec. 6-151(a)(1), Buildings and Building Regulations (Chapter 6) – incl. short-term rental registration, p. 39
Rental units must be registered in accordance with this article by January 1st of each year; Rental units entering the rental housing market must be registered within fourteen days.
- Sec. 6-150.1 (Owner-Occupied), Buildings and Building Regulations (Chapter 6) – incl. short-term rental registration, p. 38
Accessory dwelling units are not considered owner- occupied units for purposes of short term rental registration and regulation.
- Sec. 6-151(d), Buildings and Building Regulations (Chapter 6) – incl. short-term rental registration, p. 43
Once registration is approved by the City, each short term rental shall be given a registration number, which much be displayed in the rental unit and in any and all advertisements for the rental unit.
- Sec. 6-152(c), Buildings and Building Regulations (Chapter 6) – incl. short-term rental registration, p. 45
Owner Occupied Short Term Units, 1st Unit - $100
- Sec. 6-152(c), Buildings and Building Regulations (Chapter 6) – incl. short-term rental registration, p. 45
Non-Owner Occupied Short Term 1st Unit - $200
- Sec. 6-153(a), Buildings and Building Regulations (Chapter 6) – incl. short-term rental registration, p. 47
Overnight short term rental guest occupancy in each rental unit will be limited to two (2) guests per bedroom plus no more than two (2) additional guests.
- Sec. 6-153(f), Buildings and Building Regulations (Chapter 6) – incl. short-term rental registration, p. 48
(f) No individual or entity may register a short term rental in any single family home unless it is owner-occupied; tenant- occupied with permission of the owner; or located on Peaks Island, or on an Outer Island.
- Sec. 6-153(b), Buildings and Building Regulations (Chapter 6) – incl. short-term rental registration, p. 47
For calendar year 2025, no more than 400 non- owner occupied mainland short term rental units shall be registered. Beginning in calendar year 2026 and for each year thereafter, non-owner occupied mainland short term rental units shall be limited to no more than 1.5% of the total number of registered long-term rental units in the prior year.
- Sec. 6-153(e), Buildings and Building Regulations (Chapter 6) – incl. short-term rental registration, p. 48
An individual or entity may only register up to five (5) short term rental units in the City, in any one (1) calendar year.
- Sec. 6-155(d), Buildings and Building Regulations (Chapter 6) – incl. short-term rental registration, p. 50
Notwithstanding the provisions of § 6-1, the penalty for such violation shall be $1,000.00;
- Sec. 6-153(b), Buildings and Building Regulations (Chapter 6) – incl. short-term rental registration, p. 47
Mainland accessory dwelling units that are registered as non-owner occupied short term rentals and that were constructed and received a certificate of occupancy within 5 years before the unit’s registration date are excluded from the 1.5% limit set forth in this paragraph.