Ontario · Architect seal requirements
Ontario Architect seal requirements: size, wording, and the rule that sets them
As of
Architects in Ontario seal under R.R.O. 1990, Reg. 27, s. 41, under the Architects Act, R.S.O. 1990, c. A.26; use of the seal governed by Reg. 27, s. 42, administered by the Ontario Association of Architects. Regulation 27 prescribes no wording, shape or size. The design is approved by the Council and the seal itself is issued by the Registrar, so the architect does not choose its dimensions.
Ontario runs three separate regulators: Professional Engineers Ontario under the Professional Engineers Act, the Ontario Association of Architects under the Architects Act, and the Association of Ontario Land Surveyors under the Surveyors Act. In all three the seal is issued by the regulator rather than made by the licensee, so there is no dimension for a licensee to choose. Section 53 of Reg. 941 was replaced in its entirety by O. Reg. 837/21 effective July 1, 2022, and the regulation is consolidated to July 1, 2026 with O. Reg. 126/26 as the last amendment. Three pieces of PEO's own material lag behind that: the "P.Eng. Seal" page on peo.on.ca attributes the sealing rule to "section 53 of the act", but the Act ends at s. 49 and the sealing provision is s. 53 of the regulation; the "Act, Regulations, By-laws" page still describes Reg. 941 as "amended to O.Reg. 332/23"; and the 2005/2008 guideline still hosted on peo.on.ca required an electronic facsimile to be "identical in size, shape, and content to the seal created by the rubber stamp", a sentence the current March 2022 guideline and the amended s. 53(3)(b) both dropped.
Ontario Architect seal
- Diameter
- Regulation 27 prescribes no wording, shape or size. The design is approved by the Council and the seal itself is issued by the Registrar, so the architect does not choose its dimensions.
- Expiration date
- Section 41 is the entire seal provision and prescribes no content at all — the design is approved by Council and the seal is issued by the Registrar, so no rule calls for an expiry date.(R.R.O. 1990, Reg. 27, s. 41)
- City on seal
- Reg. 27 prescribes no wording for the architect's seal, so nothing requires a city; and a member cannot have a seal made, only obtain one from the OAA.(R.R.O. 1990, Reg. 27, ss. 1 and 41)
- A member who holds a certificate of practice, belongs to a partnership that holds one, is an employee required to use a seal in that capacity, or is an officer, director or full-time employee of a certificate of practice holder who personally supervises and directs the practice of architecture, is entitled on application and payment of the fee prescribed by the by-laws to be issued a seal in a design approved by the Council.(R.R.O. 1990, Reg. 27, s. 41(1))
- The Regulation defines "seal" as a seal issued by the Registrar, and using a seal that has not been issued under the Regulation is professional misconduct.(R.R.O. 1990, Reg. 27, s. 1; s. 42, para. 18)
- The ownership of every seal issued by the Association is retained in the Association, and the seal must be returned to the Registrar on cancellation, revocation or suspension of a license, certificate of practice or temporary license, on dissolution of the firm, or when the member no longer needs the seal in the capacity of an employee.(R.R.O. 1990, Reg. 27, s. 41(3); s. 42, para. 22)
- Failing to affix the seal and signature, through the imprint of the seal, to every design prepared under the member's personal supervision and direction and issued or exhibited to a person who is not a holder — whether submitted as part of a building permit application or issued for the construction, enlargement or alteration of a building — is professional misconduct, except in an open competition in which anonymity is a requirement.(R.R.O. 1990, Reg. 27, s. 42, para. 21)
- Affixing a seal, or permitting one to be affixed, to a design that was not prepared in its entirety under the personal supervision and direction of a member or a temporary license holder is professional misconduct.(R.R.O. 1990, Reg. 27, s. 42, para. 19)
- The OAA supplies high-resolution images of the member's seal in several file formats when it issues the seal; a member who uses the image must ensure it is not altered in any way and is applied clearly.(OAA Regulatory Notice RN.01, Version 7.0 (January 1, 2025))
- Every digitally authenticated document should display the OAA-issued seal as proof of authority; the notice's other standards for digital authentication are that the platform comply with the laws respecting electronic commerce, that it should offer strong data encryption, audit trails and multi-factor authentication, and that electronic signatures should provide traceability for identity verification.(OAA Regulatory Notice RN.01, Version 7.0 (January 1, 2025))
- When a seal is returned to the Registrar every image of it must be deleted from all storage and the Registrar advised in writing, and seal images must be removed from drawing files before those files are shared with consultants, owners or contractors.(OAA Regulatory Notice RN.01, Version 7.0 (January 1, 2025))
- Record and as-built drawings must never be sealed, and the professional seal is not a "business seal" for fee proposals, business letters or contracts.(OAA Regulatory Notice RN.01, Version 7.0 (January 1, 2025))
Ontario architect seal questions
Can an Ontario architect order their own seal?▾
An architect cannot have a seal made. Reg. 27 defines "seal" as a seal issued by the Registrar, and using a seal that has not been issued under the Regulation is listed as professional misconduct. (R.R.O. 1990, Reg. 27, s. 1; s. 42, para. 18)
May every licensed Ontario architect apply a seal?▾
No — holding a licence is not the qualification. Section 41(1) entitles a member to a seal only if the member holds a certificate of practice, belongs to a partnership that holds one, is an employee of the Crown of Ontario or of Canada, a crown agency, a sole proprietorship, a partnership or a corporation and is required to use a seal in that capacity, or is an officer, director or full-time employee of a certificate of practice holder who personally supervises and directs the practice of architecture. A member outside all four descriptions has no route to a seal and so has nothing to apply; the only other entitlement in the section is s. 41(2), for a holder of a temporary licence. The entitlement is tied to that qualifying capacity and ends with it — including when an employee is simply no longer required to use one — so the authority to seal does not run with the licence. (R.R.O. 1990, Reg. 27, ss. 41(1) and 41(2); s. 42, para. 22)
How big is an Ontario architect's seal?▾
No regulation says. Section 41 is the entire seal provision and it prescribes no wording, no shape and no size — the design is approved by the Council and the seal itself is issued by the Registrar, so the dimensions were never the architect's to choose. The two-inch figure that circulates comes from the OAA's own Application for Seal, which describes the physical stamp products the Association sells: one has a two-inch diameter circular base and the other is a rubber stamp measured by its handle and case. Those are product dimensions, not a prescribed size for the impression. (R.R.O. 1990, Reg. 27, s. 41; OAA Application for Seal — Architect (OAA-08-22))
Can an Ontario architect seal a record or as-built drawing?▾
The OAA's answer is categorical: record or as-built drawings must never be sealed. The seal is for designs produced in connection with rendering architectural service, and the Association states it is not a "business seal" for fee proposals, business letters or contracts, and must never be applied to title blocks on blank drawing sheets, blank letters, or any other incomplete or unchecked document. Sealing an as-built set to show who drew it is exactly the use the notice rules out. (OAA Regulatory Notice RN.01, Version 7.0 (January 1, 2025))
Must an Ontario architect remove the seal image from shared drawing files?▾
Yes, and this is the trap in a CAD or BIM workflow. Before drawing files are shared with consultants, owners, contractors or any other party to the project, the files must no longer contain the seal image, and the seal information must be removed in its entirety. The OAA supplies high-resolution images of the seal in several file formats when it issues one, on the condition that the image is not altered in any way and is applied clearly; and when a seal is returned to the Registrar, every image of it must be deleted from every storage device and electronic folder and the Registrar advised in writing that this has been done. (OAA Regulatory Notice RN.01, Version 7.0 (January 1, 2025))
Can an Ontario architect seal only part of a design?▾
No. Affixing a seal, or permitting one to be affixed, to a design that was not prepared in its entirety under the personal supervision and direction of a member or a holder of a temporary licence is professional misconduct — there is no mechanism for sealing the portion you are responsible for and disclaiming the rest. Ontario engineers work the other way: their regulation contemplates a practitioner assuming responsibility for part of a document's engineering content, provided suitable text in the immediate vicinity of the seal identifies which part. Reading that arrangement across to architecture is a misconduct finding waiting to happen. (R.R.O. 1990, Reg. 27, s. 42, para. 19; cf. R.R.O. 1990, Reg. 941, s. 53(6))