Mastering AWS SES Best Practices: Scaling Limits & Ensuring High Deliverability

Scaling Amazon SES: It’s Faster Than You Think

A common misconception about Amazon SES (Simple Email Service) is that scaling sending limits is a slow and bureaucratic process. Many assume they’ll be stuck at a few thousand emails per day for months, painstakingly waiting for AWS to increase their quota. But here’s the reality: with the right approach, you can scale from sandbox limits to sending millions of emails per month in days—sometimes within 24 hours.

The real challenge? Deliverability. Getting higher sending limits is meaningless if your emails land in spam folders or get blocked by inbox providers. AWS SES is extremely unforgiving when it comes to bounce rates, spam complaints, and sender reputation. Many SES users focus on sending volume but neglect deliverability, leading to AWS suspending their accounts before they ever reach their targets.

So how do you increase sending limits efficiently while ensuring your emails actually land in inboxes? This guide covers the best practices for scaling SES limits, maintaining a pristine sender reputation, and maximizing deliverability.

Step 1: Exiting the SES Sandbox

Every new AWS SES account starts in a sandbox with strict sending restrictions. You can only send emails to verified addresses, and your daily sending quota is limited. To start scaling, you need to request sandbox removal through the AWS Support Console.

How to Get Out of the SES Sandbox Fast

1. Submit a sending limit increase request under AWS Support → Service Quotas → SES Sending Limits.
2. Clearly describe your use case (e.g., transactional emails, newsletters, customer updates).
3. Prove your sending reputation by sharing data from past email providers (bounce rates, complaint rates, engagement metrics).
4. List your email acquisition methods (double opt-in, user consent policies) to assure AWS you won’t spam users.
5. If moving from a provider like Salesforce Marketing Cloud, Mailchimp, or SendGrid, include your historical sending data.

AWS usually responds within 24 hours—sometimes faster if your request is well-documented.

Step 2: Scaling to Higher Sending Limits (1M+ Emails/Month)

Once you’re out of the sandbox, AWS starts you with a 50,000 emails per day limit (1.5M emails per month). But what if you need millions of emails per month?

How to Increase AWS SES Sending Limits Quickly

• Engage AWS Support Proactively – SES sending limit increases are not automatic. You need to request them at regular intervals.
• Prove Your Reputation – AWS will analyze your bounce rates, complaint rates, and engagement metrics before granting increases. Keep your bounce rate below 5% and spam complaints below 0.1% to avoid triggering AWS monitoring.
• Use a Dedicated IP (if sending over 100k/day) – Shared SES IPs are unpredictable. A dedicated IP helps control reputation and ensures email consistency.
• Warm Up Sending Volumes Gradually – Jumping from 50K to 500K emails/day overnight raises red flags. Increase volume by 20%-30% per week to build a strong sender reputation.

AWS’s internal thresholds mean multiple requests may be needed before you reach your desired limits. Some large senders work with an AWS Technical Account Manager (TAM) to expedite the process.

Step 3: The Hidden Challenge—Deliverability, Not Limits

Scaling SES sending limits is only half the battle. If your emails aren’t landing in inboxes, those higher limits are worthless. SES monitors your email reputation aggressively, and if you cross their bounce or complaint rate thresholds, your sending will be throttled or suspended entirely.

Best Practices for High Email Deliverability in SES

1. Clean Your Email List Aggressively

The #1 reason SES users get banned? High bounce rates.

• Remove inactive and invalid emails before sending.
• Use list cleaning tools like ZeroBounce, NeverBounce, or AWS’s own suppression list API.
• Upload past known bounces to AWS SES’s suppression list to avoid first-send issues.

2. Authenticate Your Emails (SPF, DKIM, DMARC)

ISPs like Gmail, Yahoo, and Outlook heavily filter unauthenticated emails.

• SPF (Sender Policy Framework) verifies SES is authorized to send emails for your domain.
• DKIM (DomainKeys Identified Mail) prevents email spoofing by signing messages.
• DMARC (Domain-based Message Authentication, Reporting, and Conformance) protects against phishing and improves domain reputation.

AWS SES provides built-in DKIM signing—enable it in your SES domain settings.

3. Use a Dedicated IP for Large-Scale Sending

SES assigns random shared IPs by default. These IPs may have bad reputations, causing your emails to be flagged as spam.

• For sending over 100K emails/day, request dedicated IPs through AWS SES.
• Monitor your IP reputation using tools like Google Postmaster Tools and Talos Intelligence.

4. Optimize Email Engagement (Avoid Spam Traps)

ISPs track how recipients interact with your emails. Low engagement can land you in spam.

• Avoid spammy subject lines (e.g., “FREE MONEY NOW!!!”).
• Personalize emails to improve open rates.
• Segment your audience and send targeted content instead of blasting all users.

AWS SES tracks open rates, click rates, and complaint rates—low engagement leads to throttling or suspension.

Step 4: Monitor & Maintain Your SES Reputation

Amazon SES has strict compliance monitoring to prevent abuse. Your SES reputation score determines if AWS allows continued sending.

How to Monitor SES Sending Health

• Use the AWS SES Reputation Dashboard – Shows your bounce rate, complaint rate, and sending limits.
• Check AWS Suppression List – AWS auto-blocks addresses that bounce too much.
• Set Up CloudWatch Alarms – Monitor sudden spikes in bounces or complaints to react before AWS throttles you.

If AWS flags your account for high bounces/spam complaints, engage AWS Support immediately. Fix the issue before AWS suspends your sending privileges.

Conclusion: Scale Smart, Send Smart

AWS SES can scale sending limits faster than most people expect—but only if you follow best practices. Exiting the sandbox is easy, but maintaining a strong sending reputation is the real challenge.

By proactively managing bounces, authenticating emails, using dedicated IPs, and optimizing engagement, you can ensure high deliverability while increasing your SES sending limits.

If your emails don’t reach inboxes, your sending quota doesn’t matter. Focus on deliverability first—then scale to millions.

Although AWS SES is a cheap option there are some pitfalls