Tax Code when transferring to new PAYE reference

An employee transfers from one PAYE reference to another within the business i.e. leaves one and starts as a new joiner on the other. If you have received a P9 for the employee on the old PAYE reference would you use the tax code from that or would you treat them as a new joiner using the P45 details

Hi,

A P9 can only be used by the employer it has been issued to. For the employees being transferred, you would need to use the tax code on the P45 until you receive a P9 advising to change the tax code or if you are starting the new tax year and need to implement the P9X instructions.

Thank you.