The couple spent time there last week before heading back to Wales, PEOPLE confirms
The modest two-bedroom, one bathroom apartment provides a perfect place for the couple to entertain friends and base themselves when in the capital, but their residence there is likely to be temporary. Insiders say that when they begin focusing on a public life in London, they are likely to take a larger space in the palace.
After settling into their apartment and spending a couple nights there last week, William and Kate, both 29, headed up to Anglesey, North Wales, which, palace officials say, will remain their main home while he is still an RAF Search and Rescue helicopter pilot.
William is hoping to graduate to captain in the RAF, allowing him to take the lead controls of the Sea King helicopter more regularly.
In Wales, they have been going about their lives, enjoying their marriage, those close to them say. Over the weekend, they had a date night at the cinema, when William took his wife to see the comedy Bridesmaids.