Get Your Tax Codes Right
This is one for anyone operating a PAYE scheme.
It is your responsibility to apply the correct tax code.
If you do not and you do not stop enough income tax from an employee, the Revenue will come after you in the first instance to collect the underpayment of tax. You can then seek to get the money back off the employee, but you won’t improve relations. And what if the employee has left? You can ask HMRC to collect direct from the employee, but you can only make them do so if you can demonstrate that you take reasonable care in ensuring you have the correct tax code.
Be warned, mistakes can get very expensive.