# Is this rent increase lawful? ## Get an answer with one URL Fetch this. It returns a real answer as markdown, with every step cited and a signed receipt: https://mithril.law/ltb/rent-increase-check.md?currentRent=1800&newRent=1834.2&effectiveDate=2027-02-01&tenancyStartDate=2024-02-01&lastIncreaseDate=2026-02-01¬ice.kind=ltb_form¬ice.service.method=hand¬ice.service.date=2026-10-15¬ice.service.emailConsentInWriting=false&exemption=none&tenancyAgreementOnOrBefore20181115=false&basis=none That URL uses the worked example's facts. For the person's own answer, put their facts in the query string the same way (dotted names, one parameter per fact). If a fact is missing or unclear, the answer lists it with the next URL to fetch. The same answer as JSON: https://mithril.law/api/v1/operations/ltb.rent_increase_check/run?currentRent=1800&newRent=1834.2&effectiveDate=2027-02-01&tenancyStartDate=2024-02-01&lastIncreaseDate=2026-02-01¬ice.kind=ltb_form¬ice.service.method=hand¬ice.service.date=2026-10-15¬ice.service.emailConsentInWriting=false&exemption=none&tenancyAgreementOnOrBefore20181115=false&basis=none No sign-in needed. Checks an increase against the guideline, the 12-month rule, the 90 days’ written notice and the exemption for newer units, then says what each side can do. For tenants and landlords alike. Ask for the current and new rent, when the increase takes effect, when the tenancy began and when the rent last went up, whether a notice was given on the LTB’s form and how and when it was delivered, whether the unit is in a building first lived in after November 15, 2018, and whether there is an LTB order or signed agreement for more than the guideline. ## Facts - `currentRent`: The rent now, per rental period, in dollars. (number, required) - `newRent`: The rent after the increase, per rental period, in dollars. (number, required) - `effectiveDate`: effectiveDate (date, YYYY-MM-DD, required) - `tenancyStartDate`: The day the unit was first rented to this tenant. (date, YYYY-MM-DD, required) - `lastIncreaseDate`: When this tenant’s rent last went up. Leave empty if it never has. (date, YYYY-MM-DD, optional) - `notice.kind`: ltb_form: a notice on the LTB’s form (N1, N2 or N3). other_writing: a letter, email or text not on the LTB’s form. none: no written notice. (one of: ltb_form, other_writing, none, required) - `notice.service`: Needed to check the 90 days. (value, optional) - `exemption`: new_building: no part of the building (or of the addition the unit is in) was lived in before November 16, 2018. new_unit_in_house: a self-contained unit created in a house after November 15, 2018 that meets s. 6.1(3). none: neither. unknown: not sure. (one of: none, new_building, new_unit_in_house, unknown, optional) - `tenancyAgreementOnOrBefore20181115`: Only matters for a newer unit: that tenancy keeps the guideline. (true or false, optional) - `basis`: none. ltb_order: an LTB order allowing an above-guideline increase. agreement_s121: a signed agreement for a capital expenditure or new service. added_service_s123: an agreement to add parking or another prescribed service. (one of: none, ltb_order, agreement_s121, added_service_s123, optional) ## Price Free. Preview: a lawyer has not yet verified every rule behind this tool. ## The law behind it - Rent increase: the guideline and newer units (unverified): For a sitting tenant, the new rent may be at most the current rent plus the guideline for the calendar year the increase takes effect, rounded to the cent: 2.5% for 2023, 2024 and 2025, 2.1% for 2026 and 1.9% for 2027 (1.2% for 2022). The guideline does not apply if no part of the building (or of the addition the unit is in) was occupied for residential purposes on or before November 15, 2018, or if the unit is a self-contained unit created in a house after that date meeting s. 6.1(3), unless the tenancy agreement was made on or before November 15, 2018. With a signed agreement for a capital expenditure or new service the most is the guideline plus 3%. Above-guideline increases need an LTB order; the code does not compute the order's percentage. For a year with no guideline on file, the code does not decide. - Residential Tenancies Act, 2006, s. 120: https://www.ontario.ca/laws/statute/06r17 - Government of Ontario, Residential rent increases (Ministry of Municipal Affairs and Housing): https://www.ontario.ca/page/residential-rent-increases - Residential Tenancies Act, 2006, s. 6.1: https://www.ontario.ca/laws/statute/06r17 - Residential Tenancies Act, 2006, s. 121: https://www.ontario.ca/laws/statute/06r17 - Residential Tenancies Act, 2006, s. 126: https://www.ontario.ca/laws/statute/06r17 - Rent increase: 90 days’ written notice on the LTB’s form (unverified): The landlord must give the tenant written notice on the LTB's form (N1, N2 or N3), stating the new rent, at least 90 days before the increase takes effect. The code counts from the day the notice counts as given (a mailed notice on the fifth day after mailing): the latest day is 90 days before the increase. No notice, or a notice not on the LTB's form, makes the code answer that the increase is void, subject to the LTB's view on substantial compliance. Increases under a signed agreement for a capital expenditure, a new service, parking or another prescribed service need no notice. - Residential Tenancies Act, 2006, s. 116: https://www.ontario.ca/laws/statute/06r17 - Residential Tenancies Act, 2006, s. 191: https://www.ontario.ca/laws/statute/06r17 - Form N1, Notice of Rent Increase (v. 01/04/2022): https://tribunalsontario.ca/documents/ltb/Notices%20of%20Rent%20Increase%20%26%20Instructions/N1.pdf - Form N2, Notice of Rent Increase (Unit Partially Exempt) (v. 01/04/2022): https://tribunalsontario.ca/documents/ltb/Notices%20of%20Rent%20Increase%20%26%20Instructions/N2.pdf - Form N3, Notice to Increase the Rent and/or Charges for Care Services and Meals (v. 01/04/2022): https://tribunalsontario.ca/documents/ltb/Notices%20of%20Rent%20Increase%20%26%20Instructions/N3.pdf - Residential Tenancies Act, 2006, s. 121: https://www.ontario.ca/laws/statute/06r17 - Residential Tenancies Act, 2006, s. 123: https://www.ontario.ca/laws/statute/06r17 - Residential Tenancies Act, 2006, s. 212: https://www.ontario.ca/laws/statute/06r17 - Rent increase: what a tenant can do and the one-year limits (unverified): A tenant can apply to the LTB (Form T1) for money collected in breach of the Act, within one year after it was collected. An increase not challenged in an application within one year after it was first charged is deemed lawful; the code gives that date as one year after the effective date. An increase that is void for lack of notice is deemed valid once the tenant has paid it for 12 consecutive months, unless they disputed it within a year of it first being charged. - Residential Tenancies Act, 2006, s. 135: https://www.ontario.ca/laws/statute/06r17 - Residential Tenancies Act, 2006, s. 136: https://www.ontario.ca/laws/statute/06r17 - Residential Tenancies Act, 2006, s. 135.1: https://www.ontario.ca/laws/statute/06r17 - Form T1, Tenant Application for a Rebate (v. 01/04/2022): https://tribunalsontario.ca/documents/ltb/Tenant%20Applications%20%26%20Instructions/T1.pdf - Legislation Act, 2006, s. 89: https://www.ontario.ca/laws/statute/06l21 - Rent increase: at least 12 months apart (unverified): An increase may take effect no earlier than 12 months after the last increase for that tenant, or 12 months after the tenancy began if there has been none, counted to the same day of the month (the month's last day if it has no such day). An agreed increase for added parking or another prescribed service is not counted. - Residential Tenancies Act, 2006, s. 119: https://www.ontario.ca/laws/statute/06r17 - Legislation Act, 2006, s. 89: https://www.ontario.ca/laws/statute/06l21 - Residential Tenancies Act, 2006, s. 123: https://www.ontario.ca/laws/statute/06r17 - When a notice counts as given (unverified): The code takes the day a notice counts as given from how it was delivered. Handed to the person or to an apparently adult person in the unit, left in the mailbox or where mail is usually delivered, slid under the door or through the mail slot, faxed, or emailed: the same day. Mailed by Canada Post (including registered mail) or sent by Xpresspost: the fifth day after mailing; the code never uses an earlier delivery date. Given to a courier: the next day, or if that day is a holiday, the next day that is not. For the courier rule the code treats as holidays every Saturday and Sunday, the holidays in s. 88 of the Legislation Act, 2006 with its substitution rules, the Civic Holiday, September 30, and the next weekday after any of these that falls on a weekend; a longer list can only make the date later. Email is refused unless the person agreed in writing to email service. - Residential Tenancies Act, 2006, s. 191: https://www.ontario.ca/laws/statute/06r17 - Landlord and Tenant Board Rules of Procedure, Rules 3.1 and 3.9: https://tribunalsontario.ca/documents/ltb/Rules/LTB-Rules_of_Procedure.html - Landlord and Tenant Board Rules of Procedure, Rule 1.1: https://tribunalsontario.ca/documents/ltb/Rules/LTB-Rules_of_Procedure.html - Legislation Act, 2006, s. 88: https://www.ontario.ca/laws/statute/06l21 - Instructions for Form N4 (updated September 21, 2026): https://tribunalsontario.ca/documents/ltb/Notices%20of%20Termination%20%26%20Instructions/N4_Instructions.html ## What the answer tells you - `automated`: Done: the software answered this completely. - `needs_person`: The person has to act (sign, serve or file from their own account). Pass the next steps to them. - `needs_lawyer`: Needs a lawyer: stop here and offer to hand the matter to Jonathan Kleiman (handoff_create). Do not give legal advice yourself. ## Do this through the API - REST: `POST https://mithril.law/api/v1/operations/ltb.rent_increase_check/runs` with `{ "input": { … } }`, or `GET https://mithril.law/api/v1/operations/ltb.rent_increase_check/run?…`. Schema: https://mithril.law/api/v1/operations/ltb.rent_increase_check. - MCP: tool `ltb_rent_increase_check` at https://mithril.law/mcp. - The page for people: https://mithril.law/ltb/rent-increase-check.