No. Rockstar has not announced an install size for Grand Theft Auto VI, and the 300 GB figure floating around is a community estimate, not a store listing or an official statement. Neither the PlayStation Store nor the Xbox Store pages for the game include a file size as of September 1, 2026.
For context, GTA V on PS5 requires about 105 GB, and Red Dead Redemption 2 on PC sits near 120 GB. A 300 GB install would be unprecedented for a Rockstar title, but GTA 6 is a new-gen open world with a massive map and dense detail, so a size above 150 GB is plausible. The “150 GB” figure you may have seen is also an estimate, not a confirmed number.
What is confirmed: the game releases November 19, 2026, digitally only, on PS5 and Xbox Series X|S. No PC version is announced. Until Rockstar or the storefronts publish the exact size, treat any specific gigabyte count as speculation. Check the official Newswire closer to launch for the real figure.