Slovakia IBAN validator
How the IBAN format works
- Format
- SK + 2 check digits + 4-digit bank code + 6-digit account prefix + 10-digit account number (24 chars)
- Example
- SK3112000000198742637541
Things to watch for
- 24 characters total, all numeric
- Same BBAN structure as Czechia
^SK[0-9]{2}[0-9]{4}[0-9]{6}[0-9]{10}$A Slovak IBAN is 24 characters, entirely numeric after the country code: “SK”, two check digits, a 4-digit bank code, a 6-digit account prefix, and a 10-digit account number. That account-prefix block is a specifically Slovak (and Czech) feature dating back to the two countries’ shared banking system before 1993 — it’s present in every Slovak IBAN even when its value is all zeros, so it’s not a segment you can safely omit or assume is filler. Anyone paying a Slovak supplier, landlord, or employee via SEPA, or entering an IBAN into a form that no longer accepts a domestic account number and bank code separately, needs all 24 digits in the right blocks.
How this validator works
This tool checks the “SK” prefix, confirms the bank-code block is 4 digits, the account-prefix block is 6 digits, and the account-number block is 10 digits, then runs the real mod-97 checksum (ISO 7064) Slovak banks use to generate a valid IBAN — entirely in your browser, nothing sent to a server, no signup required, result as you type.
What a pass doesn’t tell you
A pass confirms the 24 digits are correctly formed and internally consistent — not that the account is open, active, or belongs to whoever you expect. This tool doesn’t resolve the bank code to an institution name and never contacts a bank or the National Bank of Slovakia. If a Slovak IBAN fails, check first whether the 6-digit account-prefix block was accidentally merged into or dropped from the 10-digit account number — that boundary is the detail most often mistyped, especially when converting from an older domestic account number that didn’t show the prefix separately.
Scope: Slovak IBAN structure and mod-97 checksum validation only — not payment processing, bank-name lookup, or confirming an account is active, none of which a client-side check can establish. Use this validator to catch a typo before a transfer fails; use your bank to confirm the account itself.
Content last reviewed 2026-07-07.
IBAN FAQ
What are the blocks inside a Slovak IBAN?
24 characters, all digits: 'SK', two check digits, a 4-digit bank code, a 6-digit account prefix, and a 10-digit account number — for example SK3112000000198742637541.
I've seen this exact same layout on a Czech IBAN — is that a coincidence?
No. Slovakia and the Czech Republic shared a single banking system before splitting in 1993 and still use the identical BBAN structure today — 4-digit bank code, 6-digit account prefix, 10-digit account number — even though the two countries' IBANs carry different country codes and checksums and aren't interchangeable.
What is the 6-digit account-prefix block for?
It's a distinct segment that further qualifies a Slovak account beyond the bank code alone. Some accounts have a prefix of all zeros; others don't — but the 6-digit block is always present in the IBAN even when its value is entirely zero, so it should never be dropped as if it were padding.