That's according to the gamemaker Thursday (February 3).
The company sold just under 19 million units over the nine months to the end of December.
That takes it past the lifetime sales of Nintendo's previous Wii console.
It was some way under total buys of the Switch a year before, but showed the ongoing popularity of the ageing console, now in its fifth year on the market.
Though Nintendo celebrated a milestone, it has faced component shortages like most other tech companies.
The Japanese firm cut its full-year Switch sales forecast to 23 million units - one million below previous estimates.
The gaming industry itself is seeing record-breaking deals.
That as new gamers enter the market and online play expands.
Nintendo hopes new major titles will help with sales, including a hotly anticipated sequel to 'Legend of Zelda: Breath of the Wild'.
The latest title in the critically acclaimed franchise is due for release this year.
