The Bank of England base rate is the single most influential number in UK mortgage pricing. It determines what banks pay to borrow from each other, which in turn determines what they charge you. But the relationship is not always direct, and the timing varies depending on what type of mortgage you hold.\n\nTracker Mortgage Holders Feel It Immediately — If your mortgage is base rate plus 0.75%, a 0.25% cut in the base rate reduces your rate from (say) 5.25% to 5.00% the following month. On a 250,000 balance, that saves roughly 33 per month. Tracker holders are the most exposed to rate changes, both up and down.\n\nFixed Rate Holders Feel Nothing Until Renewal — The whole point of a fixed rate is insulation from rate movements. Whether the base rate rises or falls during your fixed period, your monthly payment stays the same. But when your fix expires and you come to remortgage, the prevailing rate environment at that point determines your next deal. If rates have risen sharply during your fixed period, the shock at renewal can be severe.\n\nSVR Holders Are at the Lender's Discretion — Standard Variable Rates do not track the base rate automatically. Lenders can change their SVR at any time, by any amount, in either direction. In practice, SVRs tend to follow the base rate loosely, but lenders sometimes absorb part of a cut or pass on more than a rise. This unpredictability is one of several reasons why sitting on an SVR is rarely a good idea.\n\nHow Fixed Rates Are Priced — Fixed mortgage rates are not set by the current base rate. They are based on swap rates, which reflect market expectations of where the base rate will be over the fixed period. A 5-year fix is priced off the 5-year swap rate. This is why fixed rates sometimes rise before the Bank of England actually moves, if the market expects higher rates ahead. Conversely, fixed rates can fall even when the base rate stays the same, if future expectations shift downward.\n\nWhat Borrowers Should Do — If you are on a tracker and rates are rising, consider locking into a fix for certainty. If you are approaching the end of a fix and rates have fallen since you last locked in, shop around early to take advantage. If you are on the SVR, you are almost certainly paying more than you need to and should act immediately. Use our comparison tool to check what deals are available for your current LTV and circumstances.