If you want leverage in your negotiation it's important to start early -- as much as four months before your renewal date. This is because your lease probably contains language stating that you must give two months’ notice before moving out or you'll incur a penalty.
We advise avoiding that trap by not waiting for your landlord to contact you, but preemptively asking via email what rent they propose for the coming year. If they don't answer in two or three days, email again. And again. And again.
When they get back to you, they'll likely quote you the extremely high "rent" on your last lease plus 2% plus the CPI (if you're under age 62). They know that you can't possibly pay this amount, so they say they'll give you a better deal if you sign a new lease.
You'll try to negotiate a better price but they'll be very slow to respond. As time passes you begin to risk having to pay penalties. The longer the delay, the more you'll be pressured to sign a lease under their terms.
You’ll be in a much stronger negotiating position if you put the landlord on the defensive by asking about next year's rent very early. If you don't like their best offer you can threaten to give notice. If they don't back down you'll have plenty of time to find a new apartment. They likely will make you a better deal before then.
The lesson -- start early to take control
NEXT: Don't get fooled