3 year rental contract

The maximum combined length of short-term rental contracts is three years. So it is not possible to extend your current contract by another year.

However, not doing anything at this point is actually the best thing you can do in your situation, if you indeed would like to stay another year.

If neither your nor the owner state otherwise, your current contract will automatically be converted to a nine-year contract, with a starting date the same as your that of your original three-year contract. So from 1 March you will in fact be in your fourth year of a nine-year contract, which means you can leave without paying any kind of penalty, by simply giving a notice of three full calendar months.

Just to add to my previous reply that your 3-year rental contract can not "start again" at the end of February, because a 3-year contract cannot be legally renewed, it having reached the maximum time allowed for short-term contracts. If your landlord has said that after three years, your contract will be renewed for another three years, he is talking rubbish.

Either you or your landlord need to have given (*) notice for your 3 year fixed-term contract to come to an end at the end of February because in Belgium (and some other continental countries) even term contracts need to be determined and in the absence of determination they automatically roll over.

In the absence of such determination your contract automatically rolls over and, by Belgian law, it rolls over into a standard "nine" year contract which has, in effect, already run its first three years. You (but not your landlord) can determine this new contract at any time without any penalty being due by giving three calendar months notice.

* The normal notice period is three calendar months, it is just possible (but unlikely) that your contract specifies a lesser period. If the standard (or a two month) notice period applies then your contract WILL automatically roll over to a standard nine year one on 1st March because neither you nor your landlord have given the required notice and you need take no further action. It would, of course, be polite to advise your landlord that you will be staying on and expect to be there for at least another year. If the specified notice period should happen to be one month, then your landlord could still give you notice (until the end of this month) to quit at the end of February but what he cannot do is to extend or renew your contract in any way other than by its conversion to a partly-run nine year contract.

As above. Your fixed 3-Year contract now becomes a standard 9-Year contract where you are allowed to 3 months notice at any time with no penalty. Any other contract would be illegal => you do not need to do anything.

"he said I can help him find a new tenant"
Given that he can't legally put such a clause in the contract, you can expect a fight on your hands at the end of the tenancy to get any of your deposit back.

Your landlord is talking rubbish again. Either he is totally misinformed or (more likely) he does know the truth but is trying it on. Whether he finds a new tenant during the three months notice you give or he finds one six months after you have left, he cannot keep one cent of your deposit for this reason (of course he can invent loads of damages to the apartment, but that's another matter..).
The only help you are obliged to give him is to make sure he can show the apartment to prospective tenants (days and times to be agreed by you and him, details on this should be in your rental contract).
Given that your landlord seems to be a bit of a crook, you should not trust anything he says, but verify from independent sources (this board is not a bad one! :-)

> How do you know so much 'J'?
Have been both a landlord and tenant. It pays to know the law.