Pattern

Regex for UK sort code

6-digit bank sort code, optionally hyphen-separated.

The UK sort code regex is ^\d{2}-?\d{2}-?\d{2}$ — copy it below, or open it in the explainer for a token-by-token breakdown.

The pattern

^\d{2}-?\d{2}-?\d{2}$

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What it matches

12-34-56
123456
40-47-84

What it doesn't match

12-34-5
1234567
AB-CD-EF

Notes & gotchas

UK sort codes identify banks and branches. 6 digits, optionally formatted as XX-XX-XX. Used for domestic transfers (along with the 8-digit account number).

Code in your language

Use the explainer's Code tab to generate ready-to-paste snippets in JavaScript, Python, Java, .NET, Go, Ruby, and PHP for this pattern.

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Token-by-token breakdown

Every part of the pattern, left to right:

Token	Meaning
`^`	start of string (or line in multiline mode)
`\d{2}`	exactly 2 times: digit (0–9)
`-?`	optional (zero or one): the literal “-”
`\d{2}`	exactly 2 times: digit (0–9)
`-?`	optional (zero or one): the literal “-”
`\d{2}`	exactly 2 times: digit (0–9)
`$`	end of string (or line in multiline mode)

About this pattern

UK identifier formats are set by HMRC, Royal Mail, and the BACS payments scheme. The regex here matches the format; full validation may need an additional checksum or lookup.

Quick usage in different languages

This exact pattern — with the correct escaping and idioms for each language:

JavaScript: /^\d{2}-?\d{2}-?\d{2}$/.test(value)
Python: re.match(r"^\d{2}-?\d{2}-?\d{2}$", value)
Java: Pattern.compile("^\\d{2}-?\\d{2}-?\\d{2}$").matcher(value).matches()
C# / .NET: Regex.IsMatch(value, @"^\d{2}-?\d{2}-?\d{2}$")
Go: regexp.MustCompile(`^\d{2}-?\d{2}-?\d{2}$`).MatchString(value)
Ruby: /^\d{2}-?\d{2}-?\d{2}$/.match?(value)
PHP: preg_match('~^\d{2}-?\d{2}-?\d{2}$~', $value)

The explainer’s Code tab regenerates these for any pattern you paste, and the downloadable cheat sheet bundles the breakdown, all seven snippets, and the pitfalls below onto one printable page.

Common pitfalls

Anchored to the whole string. This pattern uses ^ and $, so it requires the entire input to match. To find it inside a longer text, drop the anchors and use the global (g) flag.
Escape it correctly per language. In Java and JavaScript strings each backslash must be doubled (\\d); in Python, Go, and C# use raw/verbatim strings so the backslashes survive.
Validate beyond format. Matching the format doesn't guarantee the value is real. Confirm the uk sort code against a source of truth (database, API, or checksum) where it matters.

Related patterns

More patterns in the United Kingdom 🇬🇧 category: