"because it would take months to get through"...

This is quite irrelevant, if you've got the room.
For example.
I occasionally like a can of beans.
Maybe once a week or two.
Tesco had an offer for 3 packs of 4 cans of beans for the price of one.
This was 80% of the price of even Tesco value beans - which I don't really like.
So, I got 18*4 cans.
Even comparing against the price of value beans, investing 14 pounds now, saved me 3 pounds.
Very, very few speculative investments can get this sort of return.

My shopping tends to look weird.
For example, last month I bought no meat, and 30Kg of flour.
Flour was on 3 for 2, and I use it regularly for breadmaking - 30Kg will last me 3 months or so.

I'd bought meat the month before, when it was half-off roasting joints, at a very good price, and won't be buying any for at least 3 months.

However.
To do this effectively, you need a large freezer, and the knowledge of what items normally cost, and to understand the offers.
For example, the 3 for 2 offer was on a wide variety of goods - however - it was 'cheapest free'. So you maximise the savings by only buying items of a similar price on the offer.
You also need to understand the alternatives.
If you like both apples and oranges, but for no good reason buy one one week, and one the other, then noticing the price may be a good plan.
Sometimes one is cheaper than the other.
If apples are on buy-one-get-one free, but oranges are cheaper, and you like them just as much - the orange is a better buy.

I'm spending about 60 quid/month on food, and eating reasonably well.
This should drop over the next months to about 50, as I hit my desired 6 month stock levels on most non-perishables.
(speedevil, Sun 13 Nov 2011, 17:45, Reply)