Deposit addresses on your account can expire if you have generated more than five of them. The oldest deposit address will automatically be set to expire in 7 days when you have generated more than five of them. If an address is set to expire, it will be clearly marked — the address will have the status “expiring #” where “#” indicates the number of days remaining before it expires. We recommend that you stop using deposit addresses that are set to expire as soon as possible.
Note the following:
Kraken is not responsible for funds sent to an expired deposit address.
You cannot currently choose which deposit addresses will expire, the oldest one is always the first one to expire.
An address marked as “Used” is OK to deposit to.