It is possible that if you have received a free Christmas lunch for many years, you will now be entitled to it as part of your terms and conditions. As a result of custom and practice, it could form part of your contract of employment. You may therefore have the right to refuse to pay for the Christmas lunch.
In any event, your employer cannot deduct the money from your pay packet. If any deduction was made without your written consent you could bring a claim for unlawful deductions of wages.
You would be best advised to speak to your trade union rep, who could take the issue up with your employer. It’s not worth losing your job over the hot lunch, whether it’s free or not.
