
The P permit is valid until further notice, so it does not have an expiry date, but the physical permit card must still be renewed periodically.
A permanent residence permit (P) is granted 'valid until further notice', meaning the right to reside does not expire the way a fixed-term permit does.
The permit card itself, however, is a physical document with a printed validity period and must be renewed when it runs out, similar to renewing a passport. Renewing the card does not mean re-applying for the permit.
Keep in mind that a permanent permit can still be cancelled or lapse in certain situations, for example if you move away from Finland permanently, so it is not entirely unconditional.
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