What is a binary serial number?

A binary serial number on a US bill uses only two different digits across all eight positions, such as 01010101 or 28822882. The arrangement can be anything as long as just two digits appear.

Is a binary dollar bill worth money?

Sometimes. A common binary on a circulated $1 may bring a small premium of roughly $5 to $20, while true 0/1 binaries, uncirculated notes, higher denominations, and star notes can reach the tens or low hundreds.

What is a trinary serial number?

A trinary serial uses exactly three different digits. It is more common than a binary and therefore typically worth less, though it's still a recognized fancy serial.

Guides · Fancy serials

Binary Serial Numbers: Are Two-Digit Serials Worth Money?

A Follow the Money guide · Updated June 2026

A binary note is a bill whose entire eight-digit serial number is built from only two different digits — think 0 1 0 1 0 1 0 1 or 7 7 9 7 7 9 9 7. The look is striking and the odds are long, which is why collectors hunt them. Here's what counts as binary and what one is worth.

What makes a serial binary

Look at all eight digits. If only two unique digits appear — in any arrangement — the serial is binary. 2 8 8 2 2 8 8 2 uses only 2 and 8, so it qualifies. The famous “true binary” uses specifically 0 and 1, which reads like computer code and is the most sought-after style.

Binary, true binary, and trinary

A plain binary uses any two digits. A true binary uses only 0 and 1 (like 10011010) and carries extra appeal. A trinary uses exactly three different digits and is more common, so it trades for less. A serial that's binary and also a radar or repeater is rarer still.

What is a binary note worth?

Ordinary binaries (any two digits) are fairly attainable and often sell for a small premium of $5–$20 on a circulated $1. True 0/1 binaries, uncirculated notes, higher denominations, and binary star notes climb into the tens to low hundreds. As always, the pattern is only worth what a collector will pay for it.

How to check your bill

Run the serial through the free Bill Value Checker and it will tell you instantly whether it's binary, true binary, trinary, or something rarer — along with a ballpark value. Want every bill checked automatically? The app does it the moment you scan a note.

Check for a binary serial Get the app

This guide is for general education and isn't an appraisal — values vary with the market and a note's exact condition. For a second opinion, post a clear photo to r/papermoney or consult a professional grader.

More guides: Radar notes · Repeater notes · Solid serials · Fancy serials