In finance, the term accretion refers to a positive change in value following a transaction; it is applied in several contexts.
When trading in bonds, accretion is the capital gain expected when a bond is bought at a discount to its par value,[1] given that, it is expected to mature at par.
In a corporate finance context, accretion is essentially the actual value created after a particular transaction.
Similarly, re mergers and acquisitions, accretion is referred to as the increase in a company's earnings per share on a pro forma basis following the transaction.
In accounting, an accretion expense is created when updating the present value (PV) of an instrument.