after exchanging contracts can anything prevent the completion and move going ahead?

[Finbar]

AKA Can I write my change of address cards yet?

[wowfudge]

Yes, a party to the deal may decide not to go ahead. If that should happen they will lose their deposit and there may be other penalties, they get sued for breach of contract, etc.

[TheGreenNinja]

Yes, either side can still pull out but would lose their deposit or have to pay a penalty.
I don't know how often it happens, I'd say you are pretty safe.

[specialsubject]

it does happen but not very often. I think you are fairly safe to set up the redirect, write the change of address cards and get packing!

[ThroughThickAndThin01]

Yes it does happen.

Death, change of mind, redundancy.

It very rarely doesn't go ahead though. Youre almost there.

[MaryPoppinsPenguins]

I've heard a few stories of people's mortgages getting pulled after exchange... I'm terrified it will happen to us and we'll lose our deposit! Seems so unfair...

[MyKingdomForBrie]

The bank can't pull the mortgage unless you some how break the terms pre completion or the lawyer has screwed up!! An offer is binding on them.

I work in property law and have only seen a house not complete on time once when the buyer was expecting funding from a business deal that didn't happen and had to locate funds in a hurry 10 days late! The seller is bound to complete if you hand over the money.

[bibbitybobbityyhat]

I've known it happen once. Family sitting in the moving van waiting for completion/keys to be handed over ... whole deal collapsed because the mortgage company of someone in the chain discovered at 11th hour that their borrower had been declared bankrupt.

[MaryPoppinsPenguins]

The mortgage offer can get pulled after exchange... There are even stories of it on here.

[ThroughThickAndThin01]

MyKingdom I can't believe that the seller can't refuse the buyers money before completion.

I was selling a house as an EA once where the buyer commited suicide after exchange. It was very sad.

I don't think all these possibilities are very cheery for the OP

[fiorentina]

If you're put at risk of redundancy the bank can pull the mortgage offer, leaving you unable to complete.