The invitation, emailed on 5 May, tells journalists it is for a "Surface event" and will kick off at 11 a.m. ET.
Various sources are suggesting newly instated Microsoft CEO Satya Nadella will be officiating, and all eyes will be on the new chief to see if he can channel the late great Steve Jobs in building excitement for a new piece of hardware.
The new small device has generally unknown specs and not much is known, but previous leaks have indicated the Surface Mini will be a 7- to 8-inch tablet that will come equipped with a stylus.
The news isn't entirely new - during an interview with tech news source The Verge, the man in charge of the Surface division, Panos Panay, said that the company was working on devices in “various shapes and sizes.”
The tech giant is finally gaining some momentum with its refreshed Surface Pro line selling reasonably well and its newly acquired Nokia phone division set to release some new and exciting handsets throughout the year.
Unfortunately it also seems this new tablet will be running Windows RT, meaning Microsoft hasn't given up on the flagging operating system... yet.
Watch this space for more information ahead of the event on 20 May.