If you're sharing the cost of the meal there's certain things you don't go for

Exactly this.

I couldn't be arsed to sit watching what everyone else orders and fuming over it for the sake of a few quid. Absolutely sucks the joy out of going out for dinner.

Yeah I can't stand this either.
I'm not mean in the slightest but recently went out with a group of 12 work colleagues.
I was driving. They had 3 cocktails each, starters, mains, puds and Irish coffees to finish. They had spent about £70 each, I'd spent about less than £20.
I'm not a big eater and I'd just had a main and a lime and soda.
Let's just split it equally they said!!
No fecking way was I sharing that bill with them. The annoying thing was the expectation that everyone would pay the same.
I just said, right I'm off now, I'll pay for what I've had and a share of the tip on my way out.
Usually I'd have offered some of them a lift home (going well out of my way) but I reassessed that too.

I might be more tolerant of family, esp if I didn't want to upset my sister.

I think people should order whatever they want when out for a meal. But I also think of some has ordered more than everyone else they should chip in extra of their own accord. In my group we usually split but of two of us hate a bottle of wine we will always factor that into our payment.

I would feel someone was taking the piss of they consistently ordered more and never offered to pay more. Sounds like you can't change the situation but you can change what you do so I would just pay for yourself from now on.

I’ve just looked at our local Wetherspoons- the large mixed grill is £13.65 and the fish and chips is £10.08 (same price as the scampi). Is this really the sort of difference you’re thinking about? Because honestly if my main was £3 more than someone else’s and there were 4-5 of us I probably wouldn’t even think to offer more money, I would assume that this was broadly equal. Obviously if someone else wanted to pay individually I’d be happy to but it’s not the sort of price difference that would make me feel like I had to insist (that would normally be if my main was more than £5 than the others as a rule of thumb).

And if you don’t like the way your BIL treats your sister and think he’s a greedy bastard, probably a good idea not to go out for meals with him once a month, more if birthdays! I think this is a family ick situation where it’s bothering you disproportionately because you don’t like him and you see too much of eachother.

Bollocks to that. I’m crap at cooking steak so having one in a restaurant is a real treat. No way would I forgo that to appease some arbitrary, made up ‘rules’.

Bill splitting is a tricky thing it’s fine when you are all on the same page but unless you have a proper conversation beforehand to say what you are paying for you just have to put up with it.

I don’t drink but my partner does so that normally evens out but I am finding now that I am also subbing people’s children’s meals one you barely notice but it quickly adds up.

Honestly with how easy it is to transfer money etc online now, we all find it better now for one person just to pay on the night, take a pic of the receipt, then share it in Whatsapp with a link to pay and everyone just pays for what they have in the days following. Avoids faffing around with multiple cards or calculators on the night itself and can just sort it the next day or so. And stops this kind of resentment.

If I was going out, I'd want to order what I actually want to eat, so if your payment method isn't allowing people to choose what they want then change it as it obviously isn't working.

Wetherspoons steak with an alcoholic drink on their menu is approx £13. A curry or burger with drink is approx £10. I couldn't get worked up about this.

I don't split the bill unless it's with a close friend or family member I know won't take advantage/it'll even up over time.
I stopped after going out with an old friendship group, as a student. I didn't have much left til payday but spent £12 on a pasta dish and a soft drink. A few people had steaks and most had numerous cocktails.
The split ended up at £40 each, they grudgingly "subbed" me when I explained I didn't have that and paid only for what I'd had. I didn't pay it back either, was a good time to learn, early on, to speak up and not just pay for others.

I wouldn’t care, it probably adds something like £2 each to a bill doesn’t it?

I agree OP, that's why I never split the bill and we always pay for our own. I don't like spending a tonne on eating out and can usually find something perfectly enjoyable for a reasonable price; im happy to pay that and don't want to subsidise someone who is evidently happy to spend more. With DH we have shared finances so just order what we want and am not bothered of course if he orders something expensive if he enjoys it as its both our money.

If I went for a much more expensive main I'd compensate by drinking water or not having dessert or something.

I generally avoid splitting costs evenly unless it coincidentally turns out that we've all ordered virtually the same.

In our groups, everyone orders what they want, and we split it - swings and roundabouts, it all works out over a lifetime

If there are kids there, we just add that onto the bill, and split between the adults.

Lunches with a friend, just take turns in
who pays.

I order whatever I actually want no matter the price. But if it's significantly more expensive I'll add a bit extra to the pot at the end.

I like having a little bit of a lot of things when eating out so often get a mixed grill or a starter platter as a main which tend to be more expensive.

If everyone is drinking alcohol I won't put in extra though as I don't drink and that evens things out.

Lobster and champagne for me if splitting the bill, but burger and fries with a banana milk shake if I've gotta stump up myself.

If you are eating at a weatherspoons you di so from the app or go to the bar therefore you can all easily order separately. I don't think I have ever split a bill in a weatherspoons.

This...

If you can't afford to split a meal where people are going to order what they want (I know lots of people who order steak when out because nothing beats a well cooked steak when out) then don't agree to split the bill.

This should be common sense. Why go out to dinner if you can't order and eat what you want?

I had a friend who used to do this, she'd often order three courses, the main would always be steak, lobster, King Prawns, an expensive glass or two of wine. She had her own beauty salon as well, and could afford to pay people to work for her, so not short of money.

She once twisted my arm to go on holiday with her, after a few days of splitting the bill I told her we had to start paying separately. She looked at me in disbelief and sat on the sunbed sulking for the rest of the holiday.

Gradually lost contact after the holiday, and looking back I can't believe I let her take advantage like that.

I think I vary how I work out paying bills depending on who I'm with. With friends for a lunch, we might go out for a 'cheapy' and say we'll both order from the fixed set lunch menu or whatever. With other people we'd have whatever we fancied and split the bill or sometimes we take turns to pay with close friends or family - we'll get it this time and you get it next etc.
I guess if I thought there'd be an issue like OP is talking about I'd have the discussion beforehand when the booking is made. Along the lines of "There's a lunch/dinner deal on at Harvester (or whatever) shall we go there and have the two course deal?" That might give you an opening to chat about that when everyone is looking at the menu on the night - a little reminder for BIL perhaps!

You say its mostly pubs and chains you go to. So it's not a swanky place where the most expensive food can cost over a hundred quid, so the rest might not notice an extra pound each for his course.

Next time don't stick around until the end, make an excuse that you have to leave earlier and just pay for what you had.

(Also - not in England so don’t really have those sorts of places)

Genuinely sorry - I wasn’t having a dig. I just haven’t seen a mixed grill since the 90s. It was a happy nostalgia thing, not trying to be mean or rude. Apologies.

I think if it roughly balances it’s fine. I don’t drink so often subsidise the drinkers, so no I don’t feel guilty if I have the steak at a couple of quid extra if it’s what I fancy (it’s not always what I fancy). If it bothers you that much just pay for your own, or stop going. I have a list of people I won’t split the bill with because they actually take the piss on booze, mind you I often try and avoid going out with them full stop. For good friends we know it equals out in the end and quite happily will split equally regardless.