Assurance is a type of professional service usually provided by CPAs. CPA firms offer much more than simple accounting services. A certified public accounting, or CPA, a firm must include at least one certified public accountant, licensed in the state where the firm operates. Assurance services can include a review of any kind of financial document or transaction, such as a loan, contract, or financial website. This review certifies the correctness and validity of the item being reviewed by the CPA. Auditing is a systematic process of objectively obtaining and evaluating evidence assertions about economic actions and events to ascertain of correspondence between those assertions and established criteria and communicating the results to interested users.

Audits can be considered a type of assurance service. However, audits are only designed to test the validity of the financial statements. Under an assurance engagement, accountants can provide a variety of services ranging from information systems security reviews to customer satisfaction surveys.

Assurance services done by accountants differ from non-assurance services. Other examples of assurance services include –

  • Accounts receivable review
  • Business risk assessment
  • Comfort letter
  • Customer satisfaction survey
  • Information systems security review
  • Internal audit outsourcing

Assurance services can test financial and non-financial information; due to this services can be classified as consulting services.