The only ways an employer can find out about your IVA are by:
Making financial checks, which must be approved by you in advance, or
Searching the public Insolvency Register, which is rare
If your employer asks to make a credit check on you, your employment contract should cover the rules for them doing this.
It may also be your employer’s policy that you have to declare an IVA if you get one. In this case, you should declare it before they run their credit check.
It’s rare that an employer will check the Insolvency Register, but this does happen sometimes. Your details will be shown on the register for the duration of your IVA and for three months after it ends. You should bear this in mind before you take out an IVA.