PCM
What it really means
Short for "per calendar month". A rent of £800 PCM means you pay £800 every month. This is the most common way rent is shown in UK adverts.
Context, tips & common mistakes
The arithmetic trap is converting weekly adverts: a rent quoted 'pw' is not simply multiplied by four. Multiply the weekly figure by 52 and divide by 12 for the true monthly cost — on a typical room that difference is a meaningful sum every month, and it is the number your standing order will actually need to cover.
When budgeting, remember the advertised pcm figure is rarely what leaving home costs: bills, council tax (unless exempt), a TV licence, broadband and contents insurance sit on top unless the advert says included. Before viewing, work out your true all-in monthly figure — agents routinely ask your income, and a common affordability check expects rent to be roughly a third of it or less.