Boyaca is a department of Colombia, one of the original nine states of the "United States of Colombia".

Boyaca is centrally located within Colombia, almost entirely within the mountains of Eastern Cordillera, although the western end of the department extends to the Magdalena River at the town of Puerto Boyaca. It has an area of 23,102 sq km (8,880 sq mi). The capital city is Tunja.

Although Boyaca had the right to issue its own postage stamps, it used the stamps of Colombia until 1902, when it issued a stamp honoring Diego Mendoza Perez. It issued a few more, the last coming in 1904. The stamps themselves remain commonly available, but authentic uses on cover are rare.