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If your employee has more than 1 job with you - or with another employer you ‘carry out business in association’ with - you may have to calculate National Insurance contributions (NICs) based on the earnings of both of their jobs.
You may not need to ‘aggregate earnings’ in this way if you can show HM Revenue and Customs (HMRC) that it’s not ‘reasonably practicable’ for you to do so.
The way you work out their PAYE tax won’t change.
You are not to do anything special unless the other is associated
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