Answer: -In a splendid, if somewhat dated, volume entitled Arthur Daley's Guide To Doing It Right, Mr Daley gives the following advice: Emergency Plumbers: don't bother calling an emergency plumber. Call a top brain surgeon. They'll charge you less and probably do a better job. This probably isn't that helpful in the present circumstance, though. The trouble is, charges vary widely by area and by firm. In this area, I'd guess around Ј50 per hour plus parts and very possibly plus VAT, too. And that may not be very accurate. I agree with Ric, though - surely local rates should apply. -googling for a plumber in North london finds http://www.able-group.co.uk/plumbing/?gclid=CJuhncXOiYcCFR-CQgodvVZYcA and they say 24/7 with no callout charge and a freefone number to call. I checked lots more, many with no callout charge, and none give the rate. One had a button to click for rates and it just said standard rates.