So for the 90% of English, Scottish and Welsh homes on a price-capped tariff (more or less everyone who isn't on a fixed rate), in simple terms, for every £100 you're currently paying, you'll pay roughly £93 from Sunday 1st October 2023.
This doesn't apply to those with a working smart meter, but if you don't have a smart meter, or it doesn't work, we suggest taking a meter reading within a few days either side of the rate change to reduce the risk of your supplier estimating you've used more at the higher rate than you actually have.
Take a picture of the meter for extra peace of mind!