Schwifty IBAN and BIC Validation

2026.3.0 · active · verified Sat Apr 11

Schwifty is a Python library for easily working with IBANs and BICs as specified by the ISO, enabling validation, parsing, and generation of international bank account numbers and business identifier codes. It is actively maintained with regular monthly or bi-monthly releases, and the current version is 2026.3.0.

Warnings

breaking Schwifty has periodically removed support for older Python versions. Python 3.9 was dropped in v2026.01.0, and Python 3.8 in v2024.11.0. The library currently requires Python 3.10 or newer.
Fix: Upgrade your Python environment to version 3.10 or a newer compatible version.
gotcha When integrating Schwifty's IBAN/BIC types with Pydantic, strict validation is enabled by default. To allow more lax validation (e.g., ignoring whitespace or formatting differences), the field must be explicitly annotated with `Field(strict=False)`.
Fix: For Pydantic models, use `iban: Annotated[IBAN, Field(strict=False)]` to allow lax validation.
breaking The base exception class for all validation failures changed from `ValueError` to `SchwiftyException` (which subclasses `ValueError`) in version 2021.01.0. While catching `ValueError` will still work, direct catches of `ValueError` might be too broad. `SchwiftyException` offers more specific error subclasses for granular handling.
Fix: Update exception handling to catch `SchwiftyException` or its more specific subclasses (e.g., `InvalidCountryCode`, `InvalidChecksum`) for `schwifty`-related validation errors.
gotcha Prior to version 2025.09.0, the Polish IBAN format override could lead to unusual bank code breakdowns when generating IBANs from individual components. This could result in incorrectly structured IBANs if not thoroughly validated.
Fix: Ensure you are using `schwifty` version 2025.09.0 or newer when generating Polish IBANs. For older versions, meticulously validate any generated Polish IBANs.

Install

pip install schwifty Standard Installation
pip install "schwifty[pydantic]" With Pydantic integration

Imports

IBAN
```
from schwifty import IBAN
```
BIC
```
from schwifty import BIC
```

Quickstart

This quickstart demonstrates how to initialize `IBAN` and `BIC` objects, access their components, and generate new IBANs. Validation happens automatically upon instantiation, raising a `ValueError` (or a more specific `SchwiftyException` subclass) for invalid inputs.

from schwifty import IBAN, BIC

# Validate and parse an IBAN
try:
    iban = IBAN('DE89 3704 0044 0532 0130 00')
    print(f"IBAN: {iban.formatted}")
    print(f"Country Code: {iban.country_code}")
    print(f"Bank Code: {iban.bank_code}")
    print(f"Account Code: {iban.account_code}")
    print(f"BIC (if available): {iban.bic}")
except ValueError as e:
    print(f"Invalid IBAN: {e}")

# Generate an IBAN
generated_iban = IBAN.generate('GB', bank_code='040004', account_code='34340004')
print(f"Generated IBAN: {generated_iban.formatted}")

# Create and validate a BIC
try:
    bic = BIC('COBADEFFXXX')
    print(f"BIC: {bic.formatted}")
    print(f"Country Code: {bic.country_code}")
except ValueError as e:
    print(f"Invalid BIC: {e}")

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