You’ll also need to keep records of your personal income. If you’re the nominated partner in a partnership, you must also keep records for the partnership. There are different rules on keeping records for limited companies.
https://www.gov.uk/self-employed-records/overview
1 If you filed a fraudulent return, there is no limit on how long you should hang onto your tax records. 2  If you claimed a loss from a worthless security, then you need to hold onto those records for seven years.
http://www.wisebread.com/to-shred-or-not-to-shred-how-long-to-keep-your-tax-records
If you didn't file a return but should have, you need to keep your tax records indefinitely. My co-worked was audited by the State of N. Carolina for a return they said he failed to file 11 years ago. He could not find his documents and the IRS doesn't keep records that long so they couldn't provide him a copy.
http://www.wisebread.com/to-shred-or-not-to-shred-how-long-to-keep-your-tax-records
Some special circumstances require that tax records be kept longer than four years. If you failed to report income, and it is more than 25 percent of the gross income you reported; then you need to keep the records relating to that income for six years.
http://smallbusiness.chron.com/long-self-employed-person-need-keep-tax-records-4254.html
Traditional accounting. Many businesses use traditional accounting where you record income and expenses by the date you invoiced or were billed. Example You invoiced a customer on 28 March 2014. You record that invoice for the 2013 to 2014 tax year-even if you didn’t receive the money until the next tax year.
https://www.gov.uk/self-employed-records/overview
1 If you didn't file a return but should have, you need to keep your tax records indefinitely. 2  If you amended your tax return to get an additional refund, you should keep your tax records for three years from the date of your amended return.
http://www.wisebread.com/to-shred-or-not-to-shred-how-long-to-keep-your-tax-records
It says that you should keep all your receipts and records for at least seven years. That's not true in all cases, but knowing what you should keep, and how long you should keep it, can be confusing and complicated.
http://www.wisebread.com/to-shred-or-not-to-shred-how-long-to-keep-your-tax-records
With this method, you only record income or expenses when you receive money or pay a bill. This means you won’t need to pay Income Tax on money you haven’t yet received in your accounting period. Example You invoiced someone on 15 March 2014 but didn’t receive the money until 30 April 2014. Record this income for the 2014 to 2015 tax year.
https://www.gov.uk/self-employed-records/overview
Self Employment Tax. The self-employed are required to pay a self-employment tax. In 2009, the self-employment tax was 15.3 percent of the first $106,800 net earnings; all earnings $106,800 are taxed at 2.9 percent for Medicare. This tax is the Social Security and Medicare tax that is normally paid by employers.
http://smallbusiness.chron.com/long-self-employed-person-need-keep-tax-records-4254.html
1 If you amended your tax return to get an additional refund, you should keep your tax records for three years from the date of your amended return.
http://www.wisebread.com/to-shred-or-not-to-shred-how-long-to-keep-your-tax-records
how long hold onto tax records self employed
A self employed have to hold their tax records for at least three years. To hold tax records for three years for self employed.