The TCF is not a lifetime diploma: what you need to know
This is one of the major differences from the DELF and DALF: the TCF is a placement test, not a diploma. Its result is therefore not permanently acquired: it is valid for two years from the date it was taken.
Why this time limit?
A person's language level evolves with practice, upward or downward. Since the TCF is designed to give an accurate snapshot of your level at a specific moment, its limited validity guarantees to the bodies that require it (universities, prefectures, Canadian authorities) that the result presented still reflects your actual level at the time of filing.
What happens after two years?
After this period, the result is no longer accepted in official procedures requiring proof of French level. You must then retake the entire test, with no exemption possible even if your level hasn't changed in the meantime.
Can you retake the TCF before it expires?
Yes, with no particular restriction on the number of attempts in most centres, subject to a minimum period between two sessions set by the exam centre (often several weeks). This is a useful option if your first result doesn't match the level required for your application, or if you simply want to update a certificate nearing expiration.
Our advice
Take the TCF as close as possible to the actual submission date of your application (immigration, university, naturalization) to maximize the useful validity period of the result. For further details on validity periods depending on the test version, refer to the official TCF page of France Éducation International.