When you move from one rented home to another, you can get housing benefit on both homes for up to four weeks if you have moved into the new home but the local authority agrees you could not reasonably have avoided liability for rent on both the new and the old home (eg because you had to accept the new tenancy and move quickly and had to give notice on your old home). This general rule applies only if you have actually moved into the new home. Exactly what it means to ‘move in’ can be interpreted in different ways. It could be enough if you have moved some furniture and personal possessions into the property ( R(H)9/05 ). This 4-week rule also applies if you move to a new home where you are not liable for rent but continue to have a rental liability on your old property.
HB Regs, reg 7(6)(d)&(7) ; HB(SPC) Regs, reg 7(6)(d)&(7)

Different rules apply in the cases below.

This rule applies if you move