AWS SES vs SendGrid vs Mailgun — Which Email Service Should You Use?

The AWS SES vs SendGrid vs Mailgun comparison is one I’ve done three times now — once as a junior dev who picked wrong, once as a tech lead trying to cut costs, and once for a client whose deliverability had tanked so badly their support emails were landing in spam. I’ve run all three in production. I’ve been paged at 2am because of all three. Here’s what I actually think.

Quick Verdict — SES for Cost, SendGrid for Features

Stop reading here if you want. Use AWS SES if you’re cost-sensitive and already in the AWS ecosystem. Use SendGrid if you need marketing and transactional email under one roof or if you want something that works well without a week of configuration. Use Mailgun if you’re building microservices and need serious inbound email parsing.

That’s the real answer. Everything below is the math and detail that backs it up.

SES charges $0.10 per 1,000 emails. That price is genuinely hard to argue with. When I moved a client’s transactional email from SendGrid’s Essentials plan to SES, the monthly bill dropped from $89.95 to under $12. Same volume, same results, dramatically different invoice.

SendGrid wins on features and ease of use. The dashboard is polished. The API is clean. The documentation doesn’t make you want to quit software development. If you’re not obsessively cost-sensitive, it’s the more comfortable choice — especially if your team includes non-developers who need to manage templates or look at engagement metrics.

Mailgun sits in a specific niche. It’s excellent. But it’s not the default answer for most use cases, and recommending it as such would be dishonest.

Pricing at Scale — The Math That Matters

Probably should have opened with this section, honestly. Pricing is usually the first thing teams argue about and the last thing they actually calculate properly.

10,000 Emails Per Month

At 10K/month, here’s the rough breakdown:

• AWS SES — $1.00/month if you’re sending from outside EC2. Free if you’re sending from an EC2 instance or Lambda. Yes, actually free.
• SendGrid — The Free tier covers 100 emails/day (about 3,000/month). For 10K you’re on the Essentials plan at $19.95/month for up to 50,000 emails.
• Mailgun — The Flex trial gives you 1,000 emails free, then pay-as-you-go at $0.80 per 1,000. So roughly $7.20 for those 9K paid emails. The Foundation plan at $35/month includes 50,000 emails — overkill at this volume.

Winner at this scale — SES if you’re on AWS. Mailgun pay-as-you-go if you’re not.

100,000 Emails Per Month

• AWS SES — $10.00/month. That’s it. No plan tiers. No gotchas.
• SendGrid — The Essentials plan caps at 100K emails for $29.95/month. But Essentials doesn’t include features like dedicated IPs or email validation. For those you’re on Pro, starting at $89.95/month for 100K.
• Mailgun — The Scale plan at $90/month covers up to 100,000 emails and includes dedicated IPs and more advanced analytics.

The SendGrid Pro vs Mailgun Scale comparison is basically a wash on price. SES wins by a factor of 3x to 9x depending on which SendGrid tier you actually need.

1,000,000 Emails Per Month

• AWS SES — $100/month. Flat. Predictable.
• SendGrid — At 1M emails you’re looking at custom enterprise pricing. Their published Pro tier tops out at 1.5M for around $749/month.
• Mailgun — Custom pricing at this volume. Expect to talk to sales.

At high volume, the SES cost advantage becomes extreme. A company sending 1M emails/month could save $7,800 per year just by switching to SES. I’ve seen that argument win budget conversations very quickly.

One thing to factor in — SES doesn’t include dedicated IPs in its standard pricing the way SendGrid Pro does. Adding a dedicated IP to SES costs $24.95/month per IP. Still usually cheaper overall, but worth including in the math.

Deliverability — Which Actually Reaches the Inbox?

Burned by an SES misconfiguration in 2021 — I launched a new sending domain without properly warming it up and watched our open rates fall off a cliff — I learned to take deliverability setup seriously regardless of which provider you’re using.

All three services can achieve excellent deliverability. The difference is in how much work it takes to get there.

AWS SES

SES deliverability requires more manual configuration. You need to set up DKIM, SPF, and DMARC yourself. You need to warm up new IP addresses gradually (SES provides a managed IP warm-up option now, which helps). You also start in a “sandbox” environment where you can only send to verified email addresses until you request production access — a step that confuses a lot of developers the first time they use it.

SES does include a Reputation Dashboard that shows complaint rates and bounce rates. The feedback loop system works well. But the responsibility for your sending reputation sits heavily on you.

SendGrid

SendGrid is easier out of the box. The onboarding flow walks you through domain authentication. Dedicated IPs come with guided warm-up schedules on the Pro plan. Their deliverability insights dashboard is genuinely useful — you can see ISP-level delivery data without digging through logs.

SendGrid also has a team of deliverability experts you can actually talk to on higher-tier plans. That’s not nothing. When you have a serious deliverability problem at 11pm before a product launch, having access to a human being is worth real money.

Mailgun

Mailgun’s deliverability is solid. Their sending infrastructure is well-maintained. They also offer Email Validation as a separate product ($1.20 per 1,000 validations, billed separately) which can help you clean lists before sending and reduce bounce rates proactively.

The Mailgun Inbox Placement testing tool — available on Scale plans — is genuinely useful for testing deliverability across major email clients before a campaign goes out. SendGrid has something similar. SES does not.

Honest take — if you configure any of these three properly, you’ll get good deliverability. SES just requires more upfront work to get there. If your team doesn’t have someone who knows what they’re doing with DNS records and bounce handling, start with SendGrid.

Developer Experience

I care about this a lot. Bad developer experience creates bugs, slows down integrations, and causes the kind of subtle mistakes that result in emails silently failing in production for three days before anyone notices.

AWS SES

SES is deeply integrated with the AWS ecosystem. If your application runs on EC2, ECS, Lambda, or anything else in AWS, the IAM-based authentication is seamless. You’re already managing IAM roles. Adding SES permissions is two minutes of work. The AWS SDK v3 for JavaScript has solid SES support. The Python boto3 library is reliable. Go, Java, Ruby — the official SDKs cover you.

The SES API itself is not the most elegant API ever designed. It’s functional and well-documented in the AWS docs, but the AWS docs have a certain density to them that takes getting used to. SES v2 (the newer API) is cleaner than the original but you’ll occasionally find Stack Overflow answers referencing the old v1 API that don’t directly translate.

Configuration Set management, event destinations, and email templates in SES all work well once you understand the mental model. That “once you understand” is doing a lot of work in that sentence.

SendGrid

The SendGrid Web API v3 is one of the better-designed email APIs out there. Clear endpoints, predictable response formats, good error messages. The official Node.js library (@sendgrid/mail) is widely used and well-maintained. The Python library is solid. The documentation includes code examples in seven languages with working copy-paste snippets.

Dynamic templates using Handlebars syntax are genuinely easy to work with. The template editor in the dashboard means your marketing team can make copy changes without touching code. That separation of concerns is underrated.

SendGrid also has a robust event webhook system. Bounce, click, open, unsubscribe events all POST to an endpoint you define. Easy to implement, well-documented, reliable in my experience.

Mailgun

Mailgun’s API is clean and REST-based. The documentation is good. The thing Mailgun does that neither SES nor SendGrid does as well is inbound email parsing — you can configure a route that parses incoming emails and POSTs the structured data (headers, body, attachments) to your application endpoint. For building email-based workflows, support ticket ingestion, or any feature where users can send email to trigger application actions, Mailgun’s inbound routing is genuinely excellent.

The mailgun.js SDK is maintained and functional. The Python SDK less so — I’ve personally fallen back to raw HTTP requests for some Mailgun integrations because the Python library was lagging behind the API capabilities. Not a dealbreaker, just a real thing that happened.

When to Use Each

Use AWS SES When

• Your application already runs in AWS and you want to keep everything in one ecosystem with unified IAM permissions and billing
• You’re sending high volumes of transactional email and cost is a primary concern — the $0.10/1,000 pricing doesn’t change at scale
• You have engineering resources to handle configuration (DKIM setup, bounce handling, suppression list management) properly
• You don’t need a polished marketing email interface — pure transactional, developer-managed

Use SendGrid When

• You need to send both marketing and transactional email from a single platform with shared or separated sending infrastructure
• Your team includes non-developers who need to manage templates, view analytics, or run campaigns without writing code
• You’re not in the AWS ecosystem and want a standalone service with a great API that just works
• Deliverability out of the box matters more than saving $50/month — the easier warm-up process and better default tooling are real advantages
• You want access to dedicated deliverability support on higher-volume plans

Use Mailgun When

• You’re building microservices or serverless functions that need lightweight, pay-as-you-go email without committing to a monthly plan
• Inbound email parsing is a core feature requirement — Mailgun’s routes system is meaningfully better than the alternatives for this
• You want email validation built into your sending workflow and don’t want to manage a separate validation service
• Your sending volume is irregular — some months heavy, some months light — and you want a pricing model that reflects that

The honest answer to this whole comparison — most teams default to SendGrid and do fine. Teams that do the math switch to SES. Teams building email-native features discover Mailgun. None of them are bad choices. But now you have the information to make the right one for your specific situation, rather than just going with whatever came up first in a Google search.