How long to keep records for tax- 5 years?

[Supersusie]

Am I right in thinking that records ( eg invoices etc) for self assessments should be kept for 5 years? I have to say I can't see the point if tax has all been paid and seems fine- but wanted to check.

I've a mountain of paperwork I'd love to ditch but just wondering....

I'm a sole trader, don't employ anyone and it's all quite simple finances.

Gov website agrees with you:
'5. How long to keep your records
You must keep your records for at least 5 years after 31 January of the relevant tax year.

Example

If you send your 2013 to 2014 tax return online by 31 January 2015, you must keep your records until at least the end of January 2020.'

The rule of thumb has always been 7 years among accountants.
Because that is how far back HMRC can go back on a whim if you get an inspection.

I regard my self employment records as loft insulation and keep some stuff for ever

I was always told 7. If space is an issue you can scan and back up all your records they don't all have to be paper.