If you complete your own Tax Return then you need to keep your records for at least 12 months after you submit the return as HMRC can look into it and query things up to 12 months on.
And it's not unheard for them to query the previous year as well if a discrepancy comes to light in the 'current' year. So I would advise to keep your Tax Return info for 2 years after the date it is submitted (not the year end date), so looking at realistically 3 years.
However if you have rental income, self employment income etc, you need to be able to produce this for the last 6 years. So again allowing for a year for the reurn to be submitted and checked you should keep this paperwork for 7 years.
Credit cards - up to you really. Is there anything on them which
you may need to refer back too a year later? I did shred mine ruthlessly a while ago. Then my card got cloned and cancelled and a replacement was issued. It means I can't access the online statements for the old card any more.
Do you keep utility bills etc? I'd say Credit card bills can be shreded about the same time you shred those (after 6 months).
I would say keep your wageslips a bit longer, especially the final one for the year. If you lose your P60 it can't be re-printed so you can at least refer back to your final payslip for the year to see the total figures.
Also if you have a final salary pension you may be asked to provide income figures for the last 10 years for them to see which 3 year period in that time you earnt the most.