A Maine professional engineer's seal must read State of Maine and Licensed Professional Engineer, and it must show your license number and your name in the exact form your license uses. The board's published format sets the diameter at 1-3/4 inches, a size the trade calls Size #1. Embossed, rubber stamp and electronically generated seals are all permitted. This page covers wording, size, devices, signing, sealed documents and expiration.
Engineer Seal Stamps compliance desk. Checked against 32 M.R.S. § 1355 and the State Board of Licensure for Professional Engineers. Sources read September 2026.
| Requirement | What the rule says | Source |
|---|---|---|
| State line | The words State of Maine. | 32 M.R.S. § 1355 |
| Identity lines | Your name exactly as licensed, plus your license number. | 32 M.R.S. § 1355 |
| Title | The words Licensed Professional Engineer. | 32 M.R.S. § 1355 |
| Diameter | 1-3/4 inches, which the trade calls Size #1. | Board publication "Approved Seal Format" |
| Where the size comes from | The rule hands size and design to the board and gives no figure of its own. | 02-322 C.M.R. ch. 2 § 9(1) |
| Approved formats | Embosser, rubber stamp, or an image produced electronically. | 02-322 C.M.R. ch. 2 § 9(1), (4) |
| Signing and dating | Required alongside the seal every time it is used. | 02-322 C.M.R. ch. 2 § 9(3), (10), (11) |
| Documents to seal | Your plans, specifications, reports and calculations, plus public filings and sets released for construction or issued for bids. | 02-322 C.M.R. ch. 2 § 9(5), (6) |
| Digital or electronic seal | Allowed. No cryptographic standard written for engineers is named. | 02-322 C.M.R. ch. 2 § 9(1), (3), (4) |
| License expiration | December 31 of each odd-numbered year. No practice on an expired license. | 32 M.R.S. §§ 1355, 1357, 1361 |
Maine is one row in our professional engineer seal requirements by state table, which sets each jurisdiction's rule side by side.
What wording must a Maine engineer seal carry?
Four items under 32 M.R.S. § 1355. Two are fixed wording: State of Maine and Licensed Professional Engineer. Two are yours: your license number and your name as licensed. Leave any one out and the seal no longer matches the statute.
Name as licensed means the name on your license record, not a nickname or a shortened version you use day to day. For more on how these items are applied in practice, see our summary of Maine PE stamp requirements.
How large is a Maine engineer seal?
A 1-3/4 inch diameter, known in the trade as Size #1. The board publishes that figure on its Approved Seal Format page. The rule text itself does not contain it, so a full citation names both sources.
The rule, 02-322 C.M.R. ch. 2 § 9(1), lets the licensee obtain a seal in the size and design the board prescribes, and stops there. The board page supplies the actual number. Anyone reading the regulation alone finds no dimension, which is why this page cites the rule and the board publication side by side.
Which devices may apply a Maine seal?
Three formats are approved: an embosser, a rubber stamp, or an image generated electronically. The board says the same thing in plainer terms, describing a seal as either a physical wet seal or one applied electronically.
That leaves room to match the device to how your documents travel. Paper sets can take an inked or raised impression, and electronic sets can take an applied image. Our article on choosing a professional engineer stamp for Maine has more on picking a device.
Must a Maine seal be signed and dated?
Yes. 02-322 C.M.R. ch. 2 § 9(3), (10), (11) requires your signature and the date to accompany the seal, so all three appear together on each sealed document rather than the seal standing alone.
Treat the seal, signature and date as one step in your issue process. That way a sheet never leaves the office carrying only one or two of the three.
Which Maine documents need the seal?
Maine's rule reaches three groups: your own work product, formal filings with public bodies, and sets issued for bidding or construction. The list comes from 02-322 C.M.R. ch. 2 § 9(5), (6).
- Work product: plans, specifications, reports and calculations that you prepared or directed as the responsible licensee.
- Public filings: any document you formally file with a public agency or other public body, or offer to file with one.
- Bid and construction sets: anything formally issued to contractors so they can bid or price the work, and any set released for construction.
Our article on Maine PE stamp guidelines adds more on applying the seal across a project.
Does Maine accept an electronic seal?
Yes. An image applied electronically is one of the three approved formats, and Maine does not name a cryptographic standard written specifically for engineers, per 02-322 C.M.R. ch. 2 § 9(1), (3), (4).
The electronic seal carries the same four required items as a physical one, and your signature and the date still have to go with it.
When does a Maine license expire, and can you seal after that?
Maine engineering licenses run out on December 31 of every odd-numbered year. After that date a licensee may not practice on the expired license, and the seal cannot be used until the license is renewed.
Put the odd-year December date in your calendar well ahead of time. Our Maine PE renewal tips cover the renewal side.
What should you send with a Maine seal order?
Your license number, your name as licensed, and your choice of device. The state line, the title and the 1-3/4 inch diameter are the same for every Maine engineer, so the only details that vary are yours.
Copy the name and number straight from your license record. For a wider view of the seal rules, our overview of Maine PE stamp rules is a useful next read.
How do you check a Maine seal before first use?
Make a test impression and measure it: the seal should come out at 1-3/4 inches across. Then read the four required items against 32 M.R.S. § 1355 and your license record.
Check the name letter by letter against the license. The words as licensed leave no room for an informal or shortened form.
Frequently asked questions
Is a 2-inch seal acceptable in Maine?
The board's published figure is 1-3/4 inches. A 2-inch device would not match the format the board prescribes, so order the 1-3/4 inch size.
What does Size #1 mean?
It is the trade name for a 1-3/4 inch seal, and it matches the diameter the board publishes for Maine engineers.
Does the Maine seal have to be round?
The board gives the size as a diameter, but the cited rules do not otherwise state a shape.
Can I seal work that my staff prepared?
Yes, when it was prepared under your direction as the responsible licensee. The rule covers documents prepared by you or under your direction, not only work you drew yourself.
Which board sets the Maine seal format?
The State Board of Licensure for Professional Engineers. It publishes the Approved Seal Format page that fixes the 1-3/4 inch diameter.
Have your license record open and order your Maine professional engineer seal in the board's 1-3/4 inch format.
