Displaying your state number and validation decal

Registration & documentation · Power & sail

A state-numbered boat must show its number on both sides of the forward half of the hull in plain block characters at least 3 inches high, contrasting with the background and reading left to right, with any state validation decal within 6 inches of the number (33 CFR 173.27, 174.15).

Where the number goes

• Paint the number on, or permanently attach it to, each side of the forward half of the boat (33 CFR 173.27(a)(1)).
• If the boat's shape means a number on the hull or superstructure wouldn't be easily seen, put it on a backing plate fixed to the forward half so it can be seen from each side (33 CFR 173.27(c)).
• Removable number plates are allowed only for manufacturers and dealers who are testing or demonstrating a boat (33 CFR 173.27(b)).
• Don't display any other number on the forward half of the boat (33 CFR 173.19).

Size, style and spacing

• Use plain vertical block characters not less than 3 inches high (33 CFR 173.27(a)(2)).
• The colour must contrast with the background so the number is distinctly visible and legible (33 CFR 173.27(a)(3)).
• Separate the letter and number groups with a space or hyphen as wide as a letter or digit other than 'I' or '1', for example DC 5678 EF or DC-5678-EF (33 CFR 173.27(a)(4)).
• The number must read from left to right, on both sides of the boat (33 CFR 173.27(a)(5)).
• The number begins with your state's two-letter code from the federal list. Some differ from postal codes: California is CF and Washington is WN (33 CFR 174.23; 33 CFR 173 appendix A).

Validation decal

• If your state issues validation decals, its rules must require them to be displayed within 6 inches of the number (33 CFR 174.15(a)).
• Your state decides the exact spot, for example whether the decal goes in front of or behind the number, so follow your state's instructions (BoatUS).

Tenders and dinghies

• A dinghy with an outboard is a vessel in its own right and normally needs its own number (33 CFR 173.11).
• Federal rules let states exempt a tender with less than 10 horsepower that belongs to the owner of a numbered boat and is used only between that boat and the shore, if it shows the parent boat's number plus the suffix 1, e.g. DC 5678 EF 1 (33 CFR 173.13(b), 173.27(d), 174.11(c)).
• Whether that tender exemption is available depends on your state. It relies on a parent boat with a certificate of number, so a documented parent boat has no number to lend; ask your state how to register the dinghy.

The rules: 33 CFR 173.11 · 33 CFR 173.13 · 33 CFR 173.19 · 33 CFR 173.27 · 33 CFR 173.33 · 33 CFR 174.11 · 33 CFR 174.15 · 33 CFR 174.23

A plain-language summary of federal rules for recreational boats, checked against the rules’ own text and a second source, and written in our own words. It isn’t legal advice. States add rules of their own, and rules change — the links above go to the current official text.