Depends how much you get for your games? Down here, £34 a game income v mileage at £0.45 per mile (door to door), £5 per game laundry fee (£10 per game where a suit is required), off set the cost of boots, kit, sports drinks / powders, training kit, 30% of any gym / swimming memberships and sessions, mileage to and from monthly mastermind meetings, £18.00 per week during the season for "working from home 10-51Hrs per week" for phone, internet costs etc, RA-FA membership, annual CFA membership and Prmoiton Scheme deposits - Think i was just short of £2.2k loss this last season.
I am self employed and have openly declared that officiaiting is one ond the sources of income that I recieve. Scare the hell out of the The FA when you send them an invoice for your match fee as they have to raise a cheque to pay you!
So directly, yes it would raise a possability of paying tax on your ref fee, but you run at loss for every game you do, so you get either a break / relief or even rebate. At small scale, £300 in your pocket is £300 in your pocket. So may miss out on Self Assessment becuse they think they are in PAYE and so it doesn't apply.
Take off your pension contributuons, charitable donations etc.
Flip side though, FA state that officials are responsible for ensuring that they pay any tax due on any incomes - so that makes it a form of wmployment, yes? So who has busniness use on their car insurance for driving to and from games ..........(also tax deductable as an additional expense due to reffing activities.....)