A more thorough explanation:

Definition: At maturity refers to the date when a debt or financial instrument becomes due for payment.

Example: If you have a bond that matures in 10 years, the at maturity date would be 10 years from the date of purchase. On that date, the bond issuer is obligated to pay the bondholder the full principal amount.

This example illustrates that at maturity refers to the date when a financial instrument, such as a bond, becomes due for payment. It is important for investors to keep track of the at maturity date to ensure they receive their full payment.