I set aside a rough budget of £600 and try spread it out in October and November.
I'll start adding one Christmas food item to the shop every week (e.g crisps, crackers, chocolates, chutney) and put them in a wicker hamper I've recycled year on year. We then open it on 15th December and have loads of nice treats stocked up ready. (Maybe £5 a week? So £60)
For Xmas lunch I do my shop with m&s, it's £50 deposit, and then I budget another 2x £50 in Oct and Nov to cover the whole order.
For decorations, we use the same artificial tree and basic decorations, but I like to do a bit of a refresh, so will spend £25 ISH and make my own. I think I'm going for bows this year, so will buy some nice ribbon and tie straight to the tree.
Christmas stockings - maybe £10 each, a nice bath/shower product, some chocolate and something novel.
Christmas presents - £100 on my DH, and then we agreed a per person budget for wider family, last year was £25 (so that's 8x£25)
And this is the first year with a baby, so probably £million on him!!
So roughly £565 plus the gazillion pounds spent on the baby 🤣
If we were going to have a drink, it would be a bottle of Bailey's and maybe some beers, but that will come from a separate dining out budget I allocate every month (we won't drink in the run up so I'll use 3 months worth of budget for it etc) so possibly another £150 towards Xmas.