Hi, thank you for your question. You should first check your tenancy agreement as this should state the notice period you must give.
If the 6 months tenancy has now ended and you have not signed a new tenancy agreement you will automatically be on a statutory periodic tenancy and the notice period will be 1 month notice, unless your agreement it specifically states in the tenancy agreement that upon expiration of the fixed-period the tenancy will continue as a contractual periodic tenancy - if that is the case you must give whatever notice is stated in the agreement.
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