"When should I renew my domain name?"
You must pay your renewal fees by the current expiration date of your domain name. We will notify you 90, 60, 30 and 0 days before your name is due to expire.
A short grace period is built into the system before the domain is deleted, but for safety sake and peace of mind it's best not to rely on that.
However, you do not need to wait until the expiration date to renew your domain name. You can renew it at any time and for any number of years up to a total of ten. With a 10 year renewal, you won't have to worry about your domain name expiring for a long long time.