Budget non-swivel/caster office chair

ikea and sit on some

Have a look and see if there are any second hand office furniture places near you - with the rise in home working theres a bit of a glut of office furniture and it'll generally be more robust and better value than Ikea and the like.

Sadly anything that is functional/ ergonomic/ is actually designed for comfort/ decent posture is expensive.

I would recommend a saddle stool.

https://www.amazon.co.uk/saddle-stool/s?k=saddle+stool

Good luck.

I spent the whole of lockdown sitting on a wooden dining chair. Except I didn't. I noticed it was a slightly curved formed wooden chair from Ikea with chrome legs. What made its supremely comfortable is the small pad of a cushion I placed on the front edge. I noticed that I perch on the end with hips rotated and that is more akin to a stool that tilts. It might be that a simple pad on the end of your current chair and legs folded underneath is all you need. Cheap to try.

I now have a second hand Vitra that is beautiful, but I perch on the end of that - as I am now typing this.

We got a posh £1000 or so chair for my son who was doing 8-10 hrs a day on it.
It was second hand and about £200.
Was a lot of money but worth it.

Have a look and see if there are any second hand office furniture places near you – with the rise in home working theres a bit of a glut of office furniture and it’ll generally be more robust and better value than Ikea and the like.

While I generally agree with the point in this case... A non swivel non caster chair is not that common and the lack of complexity means less cheapness issues. We have two IKEA ones that have proved surprising resilient because they aren't complicated.

Currently sitting on Ikea chairs. The nearest store is an hour away and don't have the time. New chair has to be a permanent feature unless it's small enough to be easily stored away. Will explore the stool options. Thank you all!