Is this a legal clause?

[beaveringaways]

Returned to work after mat leave having worked for my company for 9 years and in a senior position, came back part time and was on a temp contract as my hours and role slightly changed. Now in a permanent job share role and have a clause in my new contract (not signed yet) that if the other half of the job share leaves then they have 3 months to fill it.
I asked for a clause to be added to confirm if they couldn't find anyone else they'd find me another role honouring my hours/pay. They've said no, in practice they would but don't put it in writing.
Is this fair and legal?

Perfectly standard, fair and legal, yes.

You can't expect them to guarantee to find you another role on the same hours and pay if they can't recruit another job share partner. You'd basically be expecting them to potentially invent a non-existent job just for you, which is not a reasonable thing to expect any business to do. Trying to replace your job share for three months is reasonable.

Ok thanks for your response, I'd just hoped I'd have some security after that long in the company, my career is now dependant on a person I have no control over staying in their role! Fingers crossed!

That presumably goes both ways, though - what happens to your job sharer if you decided to leave?

Your role is not dependent on that person, it's dependent on your company filling the vacancy,

As a pp said, you can't expect them to find you another role if one isn't available. I can see why they said no.

Yes @EBearhug she will live with the same uncertainty as me too then! I'm not blaming her in any way if anything I'd like us both to be protected

If your job share partner leaves, and they cannot recruit a replacement, but there is, at that time, a role available which is suitable for you and on the same terms and conditions, you may well have a claim for unfair dismissal if they don't then redeploy you into it.

But you can't expect them to create a role just for you if there isn't one there. Businesses wouldn't be sustainable if they had to offer that kind of guarantee to people.