Tenant going on holiday- must landlord be notified?

[newsagent]

We rent a house and we will be going away for 3 weeks. Is is necessary to inform the Landlord?

A family member will be keeping an eye on the place.

I wouldn't want to think of them snooping around the house while we were away.

[Paragon]

Your contract should tell you. Most say 28 days, but have seen some for less.

[jeffrey]

We rent a house and we will be going away for 3 weeks. Is is necessary to inform the Landlord?

A family member will be keeping an eye on the place.

I wouldn't want to think of them snooping around the house while we were away.

Legally required: no.
However, it would be a sensible precaution. For instance, property insurance policies often demand that the policyholder should notify the insurer when leaving an insured property vacant; L could not do that (and so the policy could be voided in the event of a claim) if T failed to notify absence.