A provision that is attached to a bond indenture setting out the terms under which a bond issuer can call or redeem the debt by buying the bond back prior to its maturity date. Callable bonds (redeemable bonds) can be paid off by the issuer before maturity date subject to the terms stipulated in the indenture. When an issuer calls its bonds (on the call date), it pays the holders the call price (often, the face value of the bonds) in addition to any accrued interest to date.