For current and continuing clients your original tax returns filed will be held onto for 10 years. Financial statements prepared 10 years. Back-up information used to prepare returns 3 years. Permanent file information (on-going worksheets) 10 years. Letters, other information correspondence and documents 3 years. For past and discontinued clients your original tax returns filed will be held onto for 3 years. Financial statements prepared 3 years. Back-up information used to prepare returns 3 years. Permanent file information (on-going worksheets) 3 years. Letters, other correspondence and documents 3 years.