A bond, which is a form of quasi-equity instrument (QE instrument), that has no fixed maturity and can continue perpetually with no principal repayment but only a coupon interest payment. Given the quasi-equity nature of such a bond, the payment of coupon is made at the discretion of the issuer (coupon payments may not be made in a year in which the issuer has accumulated losses or does not have sufficient reserves for such payments.)

Although not redeemable, these bonds pay a steady stream of interest in perpetuity. Because of the characteristics of these bonds, they are often perceived to be a type of equity and not a debt. Issuers pay coupons on these bonds forever. Perpetual bond cash flows are assumed to come up for a perpetuity.

This bond is also known as a perp or a consol bond.