$ man google-sending-limits

Google: 25/day Start, 30 Ramp

Google Workspace mailboxes can start sending at 25 emails per day and ramp to 30 after warmup. Google is more forgiving than Microsoft, but still has limits. Exceeding them triggers throttling or spam classification.

Google gives you more headroom than Microsoft, but it's not unlimited. Starting at 25/day is the sweet spot — enough volume to be useful, low enough to stay under the radar. Ramping to 30 after warmup gives you incremental capacity without pushing into risky territory. Some people push to 40-50/day. I don't. The risk isn't worth the marginal volume.

Google Workspace mailboxes in Instantly start at 25/day. After 2-3 weeks of warmup with good engagement (opens, replies in the warming pool), I bump to 30. That's the ceiling. With 18 Google mailboxes sending 30/day, that's 540 emails/day from Google infrastructure alone. Plenty for most campaigns. If I need more, I add mailboxes — I don't increase per-mailbox limits.