Data Command Failed 550 5.4.5 Daily User Sending Quota Exceeded

title: Data Command Failed 550 5.4.5 Daily User Sending Quota Exceeded
description: Understand and resolve the Gmail 550 5.4.5 daily sending quota exceeded error in SalesBlink.

Overview

This error means your Gmail account has hit its daily sending limit. Gmail enforces these limits to prevent spam and protect account security. Once the limit is reached, all outgoing mail is blocked until the quota resets, but you can still receive emails and access your account normally.

Gmail daily sending limits

Since SalesBlink connects via SMTP/IMAP, the limits that apply to you are:

• Free Gmail accounts: 500 messages per day, 500 recipients per day
• Google Workspace accounts: 2,000 messages per day, 10,000 total recipients per day

Learn more from Google.

How to fix it

1. Wait 24 hours — limits reset on a rolling 24-hour period, not at a fixed time of day. No action is required; sending will resume automatically once the quota resets.
2. Lower your daily sending limit in SalesBlink — go to your sequence or email sender settings and reduce the number of emails sent per day to stay within Gmail's limits.
3. Spread sends across multiple inboxes — if you need higher volume, distribute your sending across several Gmail accounts in SalesBlink rather than relying on one.

Why you might be hitting the limit faster than expected

Even if your sequence volume looks low, these factors can quietly eat into your daily quota:

• Bounced emails still count toward your sending limit before they bounce back
• CC and BCC recipients each count individually toward your daily recipient total
• Replies and auto-forwards from your account also count toward the limit
• New or low-activity accounts may have lower initial limits until Google establishes a sending history

Preventing it from happening again

• Keep daily sends comfortably below your account's limit to give yourself a safe buffer.
• Ensure your email list is clean and up to date, as high bounce rates can trigger additional restrictions beyond the quota error.
• Avoid sending large volumes in a single burst; spread sends throughout the day.

Still hitting the limit after waiting?

If your account remains blocked after 24 hours, it may have been suspended rather than just rate-limited. Google Workspace admins can check and restore suspended accounts here: Restore a suspended Gmail account.

If you are on a free Gmail account, contact Google Support directly.

Updated on: 18/08/2026