Assigned number format
Connecticut assigns numbers in the pattern CT 1234 AA, using the CT prefix. Format is two letters, 1–4 numerals, then 1–2 letters.
State Requirement Summary
Connecticut Boat Registration Number Requirements
Boats registered in Connecticut display a CT-prefixed number such as CT 1234 AA. Connecticut calls for characters 3 inches high in plain block / clearly legible characters, reading left to right, contrasting color, positioned each side at the bow / forward half. Our lettering is designed to meet the displayed Connecticut size and formatting requirements. The state itself issues the validation/expiration decal — we supply the registration-number lettering.
Boat number requirements
Last regulatory review: August 22, 2026
Assigned number example
CT 1234 AA
- Minimum character height
- 3 inches
- Lettering style
- Plain block / clearly legible characters
- Contrast
- Contrasting color
- Spacing / separator
- Space or hyphen between character groups
- Reading direction
- Left to right
- Number location
- Each side at the bow / forward half
- Validation decal
- Display state-issued validation decals as directed; do not assume an offset without current DMV instructions
- State agency
- Connecticut DMV / Connecticut DEEP
What we sell vs. what the state issues: RegistrationDecals.com supplies the registration-number lettering, designed to meet the displayed Connecticut size and formatting requirements. Connecticut DMV / Connecticut DEEP issues the official validation/expiration decal — and any separate stickers such as aquatic-invasive-species, mussel-awareness, carbon-monoxide or lake-protection stickers, which are not interchangeable with each other.
Design your CT numbers
Starts with the Connecticut format (CT 1234 AA). Tap the decal and type your own assigned number exactly as it appears on your certificate of number.
Tap the decal to edit
Decal color
We supply the registration-number lettering, sized to the displayed Connecticut requirements. Connecticut DMV / Connecticut DEEP issues the validation decal.
Connecticut placement diagram
Both sides of the hull carry the number. The grey square marks where the state-issued validation decal goes — display state-issued validation decals as directed; do not assume an offset without current dmv instructions.
- Height: 3 inches, plain block / clearly legible characters
- Spacing: Space or hyphen between character groups
- Location: Each side at the bow / forward half
- Validation decal: Display state-issued validation decals as directed; do not assume an offset without current DMV instructions
Diagram is illustrative. Confirm exact positioning against the instructions issued with your Connecticut registration.
Official source
Connecticut DMV / Connecticut DEEP — Primary state agency source. Last verified August 22, 2026 (source check 2026-08-22).
Connecticut DEEP — Boating in ConnecticutRegistration requirements can change. RegistrationDecals.com summarizes publicly available boating-registration requirements to help boat owners select and display registration numbers. Always compare your registration and decals with the current instructions issued by your state boating or registration agency before applying them to your vessel.
Connecticut rules in detail
Minimum character height
Connecticut specifies characters 3 inches high. Measure the character body itself — if the state excludes borders, outlines or shading, decorative trim does not count toward the minimum.
Required lettering style
Plain block / clearly legible characters, reading left to right. Script, italic and decorative treatments are not what this style describes.
Contrast requirement
Contrasting color. In practice that means dark characters on a light hull and light characters on a dark hull, checked in daylight from the side of the vessel.
Spacing and separator
Space or hyphen between character groups. Example: CT 1234 AA. Running the groups together with no separation does not match the stated format.
Placement on the hull
Each side at the bow / forward half. The assigned CT number stays with the vessel under the Connecticut system.
Validation decal placement
Display state-issued validation decals as directed; do not assume an offset without current DMV instructions. The validation or expiration decal is issued by Connecticut DMV / Connecticut DEEP — RegistrationDecals.com supplies the registration-number lettering only.
Common mistakes
- Ordering the number without the CT prefix or the suffix letters.
- Characters shorter than the stated minimum (3 inches) so they fit inside a narrow accent stripe.
- Using a script, italic or shadowed style instead of plain block / clearly legible characters.
- Losing the required separation between the groups — space or hyphen between character groups.
- Placing the state validation decal somewhere other than the position Connecticut describes: display state-issued validation decals as directed; do not assume an offset without current DMV instructions.
Frequently asked questions
What does a Connecticut boat registration number look like?
Connecticut numbers follow the pattern CT 1234 AA, using the CT prefix, a numeral group, and suffix letters.
How tall do Connecticut boat registration numbers have to be?
3 inches, measured on the character itself, in plain block / clearly legible characters.
What lettering style does Connecticut require?
Plain block / clearly legible characters, reading left to right, and contrasting color.
How much space goes between the letters and numbers in Connecticut?
Space or hyphen between character groups. Example: CT 1234 AA.
Where do the numbers go on the boat in Connecticut?
Each side at the bow / forward half. The assigned CT number stays with the vessel under the Connecticut system.
Where does the Connecticut validation decal go?
Display state-issued validation decals as directed; do not assume an offset without current DMV instructions. The decal itself is issued by Connecticut DMV / Connecticut DEEP; we supply the registration-number lettering.
Who regulates boat registration numbers in Connecticut?
Connecticut DMV / Connecticut DEEP. Confirm the current instructions issued with your registration before applying anything to your hull. Last regulatory review: August 22, 2026.
Can I order Connecticut boat registration numbers online?
Yes. Enter your assigned CT number in the designer on this page, pick a color that contrasts with your hull, and we cut a matched port-and-starboard pair and ship it to the 48 contiguous states.
Do I need two sets of Connecticut registration numbers?
You need the number displayed on both sides of the vessel — each side at the bow / forward half — so every order ships as a matched port-and-starboard pair.
Related guides
Ready to design your CT numbers?
Our designer starts with plain block characters and proper group spacing, so you can see exactly how CT 1234 AA will read on your hull before you order.
Source: Connecticut DMV / Connecticut DEEP · Primary state agency source · Primary · Source last checked 2026-08-22.
Registration requirements can change. RegistrationDecals.com summarizes publicly available boating-registration requirements to help boat owners select and display registration numbers. Always compare your registration and decals with the current instructions issued by your state boating or registration agency before applying them to your vessel.