What happens to a domain's validity period after a transfer?

The rule depends on the extension:

• for .RO domains, a transfer between agents does not change the domain's expiration date — the period stays exactly the same as before the transfer, since RoTLD is not a registry that adds extra time on transfer;
• for many generic extensions (.COM, .NET, etc.), under ICANN policy, a transfer between registrars automatically adds 1 year to the domain's current validity period (with exceptions for domains registered/transferred in the last 60 days, or already at the 10-year maximum);
• for .EU domains, a transfer between agents generally does not change the expiration date.

You can always check your domain's updated expiration date in your EUReg customer account right after the transfer completes.