Yes. A contract signed with a secure electronic signature is valid as a rule and produces the same legal effect as a wet-ink signature. That equivalence comes from the Electronic Signature Law (No. 5070). Registered electronic mail (KEP) does a different job alongside it: it proves that a declaration was sent and that it reached the other side.
There are exceptions, and they matter. Transactions the law subjects to an official form or to notarial approval cannot be concluded with a secure electronic signature — the sale of immovable property, marriage, and certain security agreements among them. The Turkish Code of Obligations (No. 6098) proceeds from freedom of form but expressly reserves those cases. We set out in a clear matrix, by transaction type, which of your contracts can be signed with an e-signature, which with KEP, and which still need wet ink.
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