Expired 120 film
Expired 120 film turns up less often than expired 35mm, but medium format shooters tend to seek it out for the discontinued emulsions that are no longer made in any format. With only eight to sixteen frames a roll, there is less room to experiment, so knowing how a batch was stored matters more here than it does in 35mm. Compare expired 120 film prices from UK retailers on Filmproof.
About Expired 120 film
What to expect from expired 120
120 has a quirk 35mm does not: the paper backing. Over long periods the printed backing can transfer its numbering onto the emulsion, leaving faint marks across frames, and the tape can dry out or the roll can loosen on the spool. That is a storage problem rather than an age problem, but it is specific to roll film and worth knowing about before buying anything very old.
Otherwise expired 120 behaves like any expired stock, losing effective speed and gaining fog and grain, and the same one stop per decade starting point applies. The larger negative is more forgiving of the extra grain than 35mm is, which is part of why expired medium format is often more usable than its age suggests.
Buying expired 120 film
Expired 120 is scarcer than expired 35mm and often priced accordingly, particularly for discontinued Fujifilm colour and slide stocks that have no current equivalent. Because a roll gives you so few frames, it is worth buying more than one from the same batch if you find something you like, since the next lot will behave differently.
Filmproof lists expired 120 separately from fresh 120 across UK retailers, with live prices per roll updated daily.