For financial years ended on or after 1 October 2012 the audit exemption threshold criteria has changed allowing more companies to avoid the need for audit.
If a company's staff headcount is no more than 50 employees and if either your annual turnover is less than £6.5 million or the value of your gross assets (fixed assets plus current assets) is no more than £3.26million it will be eligible for small company audit exemption. These thresholds also apply to LLPs. An audit may still be required under the constitution or by a third party such as a lender. It may also be seen as desirable to ensure that the business has a robust external financial interrogation annually.
Further relaxations have occurred for subsidiary companies. Simplistically speaking if a parent company is prepared to guarantee the subsidiary's debts then audit exemption may also apply.