To think DS shouldn't be left out of play dates for this reason?

Good suggestions about hosting the occasional get together for multiple friends at once. I would also casually mention to the other parents that you're sorry you're not able to reciprocate regularly due to the circumstances. I'm sure the other parents would be understanding if they knew the reason. If you just never invite the other children back without any explanation, they will probably start to assume your DS is not that keen on theirs.

You don't have him any weekends ?

Only week day nights

Does he do an activity every night ?

We do 2 a week so can have time to self - play dates as well as time to do homework a

Why on earth not? Is his dad's house dangerous?

Can you not have a friend round after school instead of him going to an activity? Or even pick them after the activity if they go together and have the friend for tea?

Can the dad organise a play date at, for example, laser quest or top golf - somewhere a group of boys can have fun. Otherwise, the likelihood is that your son will miss out on play dates as reciprocity is key.

You say he’s new to the school - do it sounds like he hasn’t been dropped from a play date circle, but hasn’t been included in one amongst his new friends?

Bit confused why you not having him weekends is linked to school, but he’s new to this school…?

Take some occasional time off, host a play date.

Unfortunately, if you want your dc invited, you have to find a way to reciprocate. After school? Holidays? Or discuss with his df this is impacting him and make a plan together?

You can't just opt out and expect other families to do all the hosting. It isn't reasonable.

It’s very different at secondary school where parents are less involved but if I were you I would insist on some weekends. Otherwise you get all the grunt work and your ex spends downtime.

His dad may not be able to host playdates at his home. But playdates don't have to be at home. Can't he arrange to take your son and his friends to the park, cinema, swimming pool, crazy golf, McDonalds, etc etc etc once in a while?

I struggle to reciprocate play dates regularly. So tend to book a day off work once a term or so and have a load of kids round after school and also take them in the school holidays. Sometimes that means having a couple of kids for the full day if their parents work. But it’s ok as it entertains my kids and makes them more likely to be included in future.
No one likes to offer out play dates and it never be reciprocated

No one really wants to do play dates, so for someone who will never, ever be able to reciprocate, I wouldn’t, or not very often. You need to offer something back. What about holidays etc

Could dad host having some friends - but go out for an activity?

Honestly the solution here to to have a chat your ex and explain the situation and arrange that you keep him one sat per month and have giant play dates on that day.
If you never have play dates it's a fact that he will be asked on less play dates if you never reciprocate.

I'm absolutely devastated about this. I cried myself to sleep over it last night.

You cried yourself to sleep rather than cancel the odd after school activity??

Isn't 10 getting to the end of the playdate era anyway? Mine was just off out playing football with friends or out on their bikes at that age onwards, or they'd hop on the bus up to the local pool, no parental involvement unless a friend was staying over. His friends were all very local though which makes a difference I think. I take it his friends aren't local?

Does he have after school activities every day? Playdates don't have to necessarily be long. It could be meeting up at the park after school, or just pick both kids up and have them for a couple of hours.

Does he go to his dad's on Fridays? Could you change to Saturday morning and have a playdate Friday afternoons ?

What about the school holidays? Are you around more then?

I used to do Fridays only (sometimes) during term time , but host loads in the holidays. People got used to that and understood. Plus , I came in really handy if they needed help because they were working.

In the short term: I think you should try hosting playdates during the holidays and half terms, taking time off work to do so if necessary. I would also "go big" if your circumstances allow: inviting a whole group of kids, organising fun activities (pizza making, ice cream sundae making, movies with popcorn, whatever might work with those particular kids). Something that makes a good impression on the kids and on the parents, and shows you're making an effort where you can.

In the long term: it's crazy that you have no weekends with your kids. Can this custody arrangement be changed?

I don't have him at weekends and after school activities and my own work, rule out weekdays.

Thats what you need to be looking at rather than thinking other parents aren’t being fair.

What are the after school activities? If you are worried about play dates, I would drop activities and start inviting his friends round after school instead.

good point how would he even go if you have no weekends? That's not usual to never have your child at weekends only.... why would they invite him if they know you don't have him?

Why don't you ever have your child at weekends? Any chance of changing your working hours?

In similar circumstances I reciprocated en masse.

So I'd take a day or evening off work and invite pretty much everyone round. Get pizza in, buy bread and cheese and grapes etc and just accept the mess.

It means you've reciprocated at least once and it really does make a difference.

Your son may have mentioned to his friends that he goes to his dads every weekend. Would these parents have his contact details?
Could he have been invited and his Dad may have declined?

You should be getting weekends! Every other. Otherwise you do all the work and none of the fun.