A Massachusetts professional engineer seal must read Commonwealth of Massachusetts and Professional Engineer, and must show your registration number and your name as registered. The printed image should measure about 1-1/2 inches across its outside diameter. You sign and date beside the seal without covering it. This page covers the seal face, size, devices, signing, sheet-by-sheet sealing, limits on what you may seal, electronic files and renewal.
Engineer Seal Stamps compliance desk. Checked against 250 CMR 5.03(1) and the Board of Registration of Professional Engineers and Professional Land Surveyors. Sources read September 2026.
| Requirement | What the rule says | Source |
|---|---|---|
| Wording on the seal | Commonwealth of Massachusetts, and Professional Engineer. | 250 CMR 5.03(1) |
| Name and number | Your name in its registered form, plus your registration number. | 250 CMR 5.03(1) |
| Size | About 1-1/2 inches across the outside of the image itself, not the die or mount. A target figure with no tolerance band. | 250 CMR 5.03 |
| Devices | Rubber stamp, embossed seal, computer generated image, or another form the Board approves. | 250 CMR 5.03 |
| Signature | Legible if written by hand; properly encrypted if digital. Either way it sits beside the seal and leaves it visible. | 250 CMR 5.03(6) |
| Date | The document is dated along with the signature. No date appears on the seal face. | 250 CMR 5.03(6) |
| Filing with public authorities | Instruments of service are sealed one sheet at a time. | 250 CMR 5.03 |
| Limits on sealing | Only work you produced or directed and supervised. Adopting outside work by unregistered people is barred. | 250 CMR 5.03(3), (5) |
| Electronic seal | Governed by a functional standard that names no product. | 250 CMR 5.03(6), (11) |
| Certificate expiration | June 30 in even-numbered years. Seal use after a lapse is not addressed. | M.G.L. c. 112, § 81N |
Massachusetts is one row in our professional engineer seal requirements by state table, which sets each jurisdiction's rule side by side.
What wording appears on a Massachusetts PE seal?
Four items: your registration number, your name in its registered form, and two fixed phrases, Commonwealth of Massachusetts and Professional Engineer. 250 CMR 5.03(1) sets that list, and it doubles as the checklist for any proof you approve.
Use your name in the form on your registration, not a shortened version you sign with day to day. Our post on Massachusetts PE stamp requirements is a related read.
How is the 1-1/2 inch Massachusetts size measured?
On the printed or pressed image, not on the die or its mount. 250 CMR 5.03 calls for an outside diameter of approximately 1-1/2 inches, which gives you a figure to build toward rather than a band with upper and lower limits.
Measure the impression on paper, since that is what the rule describes. A die whose mount is larger than 1-1/2 inches is fine as long as the image it leaves comes out close to that size.
Which devices can apply a Massachusetts engineer seal?
A rubber stamp, an embossed seal, a digitized seal in the form of a computer generated image, or another form the Board approves. 250 CMR 5.03 lists all of these in a single provision, so the device is your choice.
On paper sets, a self-inking or traditional rubber stamp fits the named rubber stamp option and shows up on copies. Our post on Massachusetts PE stamp guidelines is a related read on device choice.
Where do the signature and date go on a Massachusetts sheet?
Next to the seal, never over it. 250 CMR 5.03(6) accepts a signature written by hand, if legible, or a digital signature that is properly encrypted. It goes beside the seal so the impression stays visible, and the document must carry a date along with the signature.
The date travels with your signature rather than with the seal face, so the die carries no date. Leave room beside the seal area on your title block for both the signature and the date.
How many sheets need a seal when you file with a public authority?
Every sheet. When instruments of service go to a public authority for filing, each one is sealed sheet by sheet under 250 CMR 5.03 and M.G.L. c. 112, § 81M, so a single sealed cover does not carry the rest of a set.
Plan your stamp use around set size. A large filing means many impressions, which favors a device that stays crisp through repeated use. Our post on accuracy under the Massachusetts PE stamp rules is useful here.
What are Massachusetts engineers barred from sealing?
Work that is not yours. 250 CMR 5.03(3), (5) limits the seal to instruments of service you produced personally or under your direct charge and supervision, and it bars adopting work by unregistered people who lacked a registrant's direct charge and supervision.
In practice this rules out plan-stamping, meaning putting your seal on outside drawings you did not prepare or supervise. 250 CMR 5.04 defines direct charge and supervision if you need the precise test.
Can a Massachusetts engineer seal and sign electronically?
Yes. The rule lists a digitized seal among the permitted forms and accepts a properly encrypted digital signature. 250 CMR 5.03(6), (11) sets a functional standard for electronic work and does not name any product.
This page does not list the criteria in that standard. Read 250 CMR 5.03(6), (11) before you choose signing software, and confirm the tool you use can meet each criterion it sets.
When do Massachusetts PE certificates expire?
On June 30 in even-numbered years, under M.G.L. c. 112, § 81N. The cited rules do not separately address using the seal after a certificate lapses, so the expiration date is the one to plan around.
Renew ahead of June 30 in even-numbered years so filings scheduled for early summer go out under a current certificate. A seal face without dates needs no change when you renew.
What should you have ready when ordering a Massachusetts seal?
Your registration number, your name exactly as registered, and your choice of device. The wording Commonwealth of Massachusetts and Professional Engineer comes from the rule, so you only need to confirm it on the proof.
Ask for the image to be built to about 1-1/2 inches outside diameter. Our posts on acquiring a Massachusetts professional engineer stamp and on Massachusetts PE stamp application steps are related reads.
How do you check a Massachusetts impression before first use?
Stamp a test sheet and measure the image, not the mount: it should come out close to 1-1/2 inches across. Then confirm all four items appear and that your name matches your registration.
Sign and date beside the test impression to be sure your signature does not obscure it, then copy or scan the sheet to confirm everything stays readable.
Frequently asked questions
Is a 1-5/8 inch seal acceptable in Massachusetts?
The rule says approximately 1-1/2 inches and sets no tolerance band, so it gives no bright line for how far off is too far. Building the image to 1-1/2 inches avoids the question.
Can the Board approve a device the rule does not name?
Yes. 250 CMR 5.03 allows another form the Board approves in addition to the rubber stamp, embossed seal and digitized seal. This page does not describe any approval process.
May I seal drawings prepared by a client's unregistered drafter?
Only if the drafter worked under your own direct charge and supervision. 250 CMR 5.03(3), (5) limits the seal to work you produced or directed, and bars adopting outside work by unregistered people.
Do sheets that never reach a public authority need the seal?
The sheet-by-sheet duty in 250 CMR 5.03 is framed around instruments of service that are filed with a public authority. The facts checked for this page do not address sheets that are never filed.
Does a scanned image of my handwritten signature count as a digital signature?
The electronic option in 250 CMR 5.03(6) is a properly encrypted digital signature, and a plain scanned image of handwriting is not encrypted. Check your method against 250 CMR 5.03(6), (11) before relying on it.
Order your seal from our Massachusetts engineer stamps and seals with your registration details at hand.
