Google Workspace SMTP Server

The Google Workspace SMTP server (often smtp.gmail.com) is the default mail transfer agent (MTA) that processes and sends all outgoing emails from user accounts within a Google Workspace organization. Its primary function is to facilitate standard business communication, not high-volume, automated outbound campaigns. It operates on a shared infrastructure with strict sending limits designed to protect the reputation of Google's IP ranges and prevent abuse.

For teams operating at enterprise scale (300k to 1M+ emails/month), understanding the limitations of the default Google SMTP server isn't optional—it's fundamental to building a sustainable outbound infrastructure.

1. Hard Sending Limits: The most significant constraint is the 2,000 emails per day limit per user. Attempting to send one million emails a month would require managing over 500 individual inboxes, which is operationally infeasible and a clear signal of abuse to Google's systems.
2. Shared Reputation Risk: Sending high-volume cold email through the standard SMTP server co-mingles your campaign traffic with critical business communications (internal, client, and transactional emails). A single campaign that triggers spam complaints can degrade the deliverability of your entire corporate domain.
3. Lack of Infrastructure Control: The Google Workspace SMTP server is a black box. You have no visibility into the underlying IP reputation, no control over routing, and no recourse if your accounts are throttled or suspended. At scale, this lack of control introduces unacceptable operational risk.

At an enterprise level, the default Google SMTP server is not a tool for execution but a component to be managed carefully within a larger infrastructure strategy.

1. Use for Initial Warmup Only: The only appropriate use for the standard SMTP server in a scaled outbound system is for the initial, low-volume warmup of new inboxes on dedicated sending domains. It helps establish a baseline of normal activity before migrating to a more robust sending infrastructure.
2. Strictly Isolate Sending Domains: Never use your primary corporate domain for any outbound activity that relies on the default SMTP server. All cold email infrastructure must be built on separate, dedicated domains to insulate your core business from reputation damage.
3. Recognize When You've Outgrown It: Teams sending 300k+ emails/month quickly discover that managing hundreds of Google inboxes is an operational nightmare. This is the point where they must transition from consumer-grade infrastructure to an enterprise-grade platform. A dedicated private email infrastructure, like SuperSend Relay, is designed for this exact purpose, handling domain rotation, deliverability, and volume without the limitations of the standard Google Workspace SMTP server.

1. Routing All Sends Through a Single Account: Attempting to bypass per-user limits by funneling all campaign sends through one or a few designated accounts. These accounts are typically suspended within hours.
2. Using the Primary Corporate Domain: The most critical error is sending cold email campaigns from your main company domain (yourcompany.com) via the default SMTP. This is the fastest way to get your domain blacklisted and disrupt all business communications.
3. Ignoring Throttling and Rate Limits: Hitting the SMTP server with rapid, unthrottled sending bursts. Google's algorithms easily detect this unnatural activity, leading to temporary account lockouts and long-term deliverability penalties.