To close your account permanently, first settle all outstanding balances and related obligations: checks, cards, installments, recurring transfers, or debit orders.
Steps
Then, submit a formal closure request to the bank using their specified method and obtain a copy or proof of payment.
Simply emptying the account is not sufficient; an empty account is not necessarily closed.
After closing, request clear confirmation and retain the request, as the Central Bank itself has reported cases where fees were incurred due to incomplete closures.
The figures, fees and limits in this answer vary by bank and change over time — confirm them with your bank or the official source before acting.