TicketMaster PhoneCharge, the ticketing agency for the Monet exhibition at the Baltimore Museum of Art through Jan. 19, 1992, plans to implement new telephone numbers in Maryland Washington and Virginia.

The change will become effective on Jan. 2, 1992. The company has also recently implemented a new 800 number for out-of-state customers.

The new 800 number, now in effect, is 1-800-551-SEAT (7328). This phone number operates only outside of the 301, 410, 703 and 202 area codes. For those callers in the Metropolitan Baltimore area, the new number, effective Jan. 2, is 410-481-7328. In the Washington area, the new number is 202-432-7328. In Northern Virginia, callers should use 703-573-7328.