When I was doing my 30-days-without-supermarkets challenge last year, I discovered that there is nothing more slippery and variable than the price of a digestive biscuit. It’s now even more slippery, to the extent that I completely gave up trying to work out who had the best deal. So back at the lab, here is my analysis of the results:
1. Iceland have a deal where you can buy 400g for the price of 300g (90p). Price per 100g = 22.5p
2. Sainsburys sell 250g of digestives for 89p – price per 100g = 35.6p
3. Sainsburys in Balham advertise a pack of 2 x 500g of digestives for £1.99 – price on the ticket, 100g = 19.9p p.
However, look closely at the packet, and you’ll find that they’re not 500g packets, they’re 400g, which means that you’re getting 2x400g = 800g for £1.99 which is 100g = 24.8p per 100g. So you’re better off going to Iceland and buying 400g for the price of 300g, thereby saving 2p. But if you don’t look carefully, you might 
look at a 250g packet for 89p, thinking that it’s the same thing as the 300g packet that was 90p in Iceland, and therefore 1p cheaper, whereas in fact, you’re getting 50g less. Confused? You bet I am. 250g of digestives often cost 99p, which is 39.6p per 100g – so if you ever did manage to buy 2x500g for £1.99 as Sainsburys advertise, then you could be paying double the price for the same product. Oh and if you buy a packet of 500g online, you can currently get that for 85p, which is better than buying two 400g for £1.99.
Update on 24/1/2013
I think I’ve sussed it now: the real price of Digestives is 99p for 400g. The reason? Because you can get Digestives in Poundland – the 400g variety, for – you guessed it, a pound. If they have to shave off the 100g from their biscuits in order to bring the price to a pound and remain profitable, then I guess 400g for £1 is the bottom line, when it comes to Digestives. And if the 99p store also has them, then the price is 99p per 400g. In short, if you’re buying 400g of Digestives, it matters very little where you buy them, except that Poundland is currently (pro rata) more expensive than Sainsburys (this week at least – last week of January) where it’s £1.70 for a double pack of 400g packets. It’s only when you buy small packets (250g) that you could be paying through the nose, and again, it doesn’t matter where you go, you’ll pay too much (though M&S local have been some of the most expensive, in my experience).
All Digestive prices trivia welcome in the comments.
