Keeping adequate records is of the utmost importance for a business, but how long should a business retain different types of records related to sales tax? As is often the answer in sales tax, it depends. Some types of records should be kept indefinitely, while other types of records should be retained according to the potential liability exposure should the records be deemed inadequate. The type of sales a business is making, as well as whether a business has a physical location or an online presence, will impact the level of difficulty associated with maintaining adequate sales tax records.
Source: taxconnections.com