The phrase "additional contract" is correct and usable in written English.
It can be used when referring to a supplementary agreement or document that adds to or modifies an existing contract.
Example: "The parties agreed to sign an additional contract to outline the new terms of the partnership."
Alternatives: "supplementary agreement" or "further contract".
We had about thirty staff foreign correspondents in about twenty bureaus and additional contract writers abroad.
They will be guarded, fed and housed by 3,500 additional contract personnel", working in 10 offices around the country.
Unions are also challenging the direct award to First Group of an additional contract for the Thameslink franchise, without any tendering process.
City records show he has been paid $1.4 million since 2001 and recently has been given an additional contract for $719,000.
See National Sand, Inc. v. Nagel Constr., Inc., 451 N.W.2d 618 (Mich .1990) (subcontractor could recover additional contract costs from engineering firm which negligently prepared plans).
In July 2011, Falcao extended his contract with the additional contract clause, and while Porto paid a £5 million commission to increase the Colombian's stay they soon made their money back, and more.
In addition Silvera & Sons seeks to establish additional contracts with importers on the West Coast of the United States and increase the volume of green coffee sold on the Brazilian market.
Additional contracts are filed in Subseries II.2: Contracts.
But lawmakers, concerned over the public outcry, put the brakes on additional contracts until next year.
Lawmakers were concerned that such companies might have access to nonpublic information that could help them win additional contracts.
Lockheed also won additional contracts valued at up to $1.2 billion for spares and sustainment of the F-35 Joint Strike Fighter program.
