26th century

The (first) Earth Empire forms, out of an Earth-centered alliance of planets. It will last until the late 30th century. Earth's single, planet-wide government is called Earthgov. (BFBS:Missing Adventures:Home)

Tensions exist between the Earth Empire and the Empire of the Draconians and even more so with the Daleks. (DW: Frontier in Space)

Earth's Moon is being used as a penal colony. (BFBS:Missing Adventures:Home)

Thanks to genetic engineering, Humans no longer have wisdom teeth. (BNA:Dry Pilgrimage)

Major Events

Unknown (mid-century)- By mid-century (probably well before), much of what was once the southern United States has sunk under the "Mississippi Sea"--probably a much-expanded Caribbean Sea. (BFBS: Home)
Unknown (mid-century)- Space travel is relatively commonplace and affordable, though trips can be lengthy. It is common practice to sedate passengers for the longer trips. (BFBS: Biology Lesson on Mal Oreille)
Unknown (late century)- Space travel appears to be significantly faster by the end of the century; the approximately 27,000 light-year trip between Earth, near the edge of the galaxy, and Dellah, near its core, takes about eleven months. (BNA: Oh No It Isn't!)

Notable individuals

Bernice Summerfield grew up in this century.
Abslom Daak and the Star Tigers fought Daleks at this time.
Ace lived here for three years when she decided to leave the Doctor and join Spacefleet.
Laura Tobin lived in this century, as a Human, before her transformation into the Doctor's companion Compassion.

Decades

25th century

Timeline

27th century