Amendment

An amendment changes the terms of a contract that is already in place. Prices change, dates move, scope grows: rather than rewrite the whole agreement, the parties sign an amendment that states exactly what is being changed and leaves the rest intact.

Because an amendment alters a binding document, it needs the same care as the original: it should reference the original contract, spell out the specific changes, and be signed by the parties. Most contracts include a clause requiring that any change be made in writing, which is why a verbal "we agreed to extend" rarely holds up. Compare an addendum, which adds new material rather than changing existing terms.