If they are in a field, and you're not near the coast, I'd say they're more likely to be Meadow Pipits, but without a picture I can't be sure at all. There is also a chance that they could be something else entirely. Do have any photos?
Home again, home again.
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Thanks Sarah. I was also thinking Meadow so that's confirmed my suspicions! It's the first time I've seen pied wagtails in the flesh and I've never seen a pipit before so I was very exciting. So much more to learn! If I get a photo next time ill post.
Meadow Pipits tend to be the predominant pipit on the coast round my way (Blackpool) in either summer or winter - they have paler legs than rock pipits, more orange colour whereas rock pipits have dark brown/black legs but they are hard to identify without close views or a good photo. To add to the confusion we get water pipits too...