coss.com vs Amazon SES
coss.com sends through Amazon SES. SES is the lower-level, lower-cost building block; coss.com adds what SES leaves to you.
SES is raw sending infrastructure: identities, configuration sets, receipt rules and tenants that you wire to S3, SNS and Lambda yourself. coss.com runs on SES, one tenant per organization, and adds the API, dashboard, contacts, broadcasts, stored inbound mail, signed webhooks and logs on top.
At a glance
Amazon SES's side was checked on against its own pages. Prices are list prices.
| Feature | coss.com | Amazon SES |
|---|---|---|
| Pricing model | Per recipient, with no volume tiers to pick: $0.40 per 1,000 recipients for the first 1,000,000; $0.30 per 1,000 recipients from 1,000,001 to 10,000,000; $0.22 per 1,000 recipients beyond 10,000,000. Paid plans start at $25/month, all of it spendable on usage | $0.10 per 1,000 emails plus $0.12 per GB of attachments, or plans with a fixed monthly charge per region; receiving $0.10 per 1,000 emails plus $0.09 per 1,000 256 KB chunks |
| Getting started | Free plan: 3,000 email recipients a month, 3,000 received emails a month and 3 inboxes; 1 sending domain. Sandbox environments with coss_test_ keys: the same API, nothing leaves coss.com | New accounts start in a sandbox per region (verified recipients only, 200 messages a day, 1 a second) until production access is granted; new AWS customers get Free Tier credits |
| Transactional email | REST API and an SMTP relay (smtp.coss.com), batch and scheduled sends, idempotency keys, templates with versions and locales | SES API v2 and an SMTP interface, templates, configuration sets |
| Marketing email | Contacts with custom properties, audiences, segments, topics with a hosted preference center and double opt-in, broadcasts on a separate marketing stream | One contact list per account with up to 20 topics and subscription management; you list contacts and call SendEmail yourself |
| Receiving email | Every environment has its own address under coss.com's inbound domain, or receive at your own domain with one MX record; an email.received webhook, content and attachments through the API | Receipt rules deliver raw MIME to S3 (up to 40 MB) or SNS (up to 150 KB), or invoke Lambda; only in some regions |
| Multi-tenant sending | Sub-accounts on Scale and Enterprise: each with its own domains, SES tenant, reputation, quotas and suppression list (transactional email) | Tenants with their own identities, configuration sets, reputation policies and optional suppression lists; up to 10,000 per account by default |
| Dedicated IPs | An add-on on Scale and Enterprise: Amazon SES managed dedicated IPs, warmed up automatically | Standard $24.95/month per IP; managed $15/month plus a per-email fee; bring your own IPs |
| Events | Standard Webhooks signatures, automatic retries, test events and `coss listen` to forward events to localhost | Event publishing through configuration sets to SNS, EventBridge, Firehose, CloudWatch or Pinpoint |
| Monitoring | Every API request, email event and webhook attempt of an environment, searchable and exportable; log drains on Scale and Enterprise | CloudWatch metrics; Virtual Deliverability Manager from $0.07 per 1,000 emails |
| SDKs | TypeScript, plus generated SDKs for Python, Go, Ruby, PHP, Java and .NET; Laravel, Rails and Django mail drivers; a CLI and an MCP server | The AWS SDKs and the AWS CLI |
Which to choose
Both are good at what they do. Here is where each one fits better.
Choose Amazon SES when
Lowest cost at volume
SES's per-email price is hard to beat when you have the engineers to build bounce handling, tracking, list management and dashboards yourself.
You're deep in AWS
IAM, KMS-encrypted receiving to S3, Lambda receipt rules, EventBridge, Mail Manager and bring-your-own IPs fit an AWS-native stack.
You need full control of the pipeline
With SES you choose every configuration set, event destination and receipt rule. coss.com makes those choices for you.
Choose coss.com when
SES without the plumbing
coss.com keeps the suppression list, does its own open and click tracking, stores received email and turns SES events into signed webhooks and per-recipient statuses.
Marketing email you don't have to build
Contacts, audiences, segments, topics with a hosted preference center, one-click unsubscribe, double opt-in and broadcasts.
Tenants, managed
Every organization and every sub-account gets its own SES tenant, with coss.com's own reputation checks, quotas and suppressions on top.
Sandbox environments
Test against the same API with coss_test_ keys and a mailbox simulator, with nothing sent and no recipient to verify.
Moving from Amazon SES
- 1
Add and verify your domains
Add each domain in coss.com and publish its DKIM and MAIL FROM records. Your SES identities keep working until you switch.
Read the guide - 2
Bring over suppressions and contacts
Export your SES suppression list and contact list and import them with coss.email.suppressions.import and coss.email.contacts.import.
Read the guide - 3
Replace SendEmail and your event pipeline
Call coss.email.send() or use SMTP at smtp.coss.com, and replace SNS or EventBridge consumers with one webhook endpoint for coss.com's events.
Read the guide
Questions
- Does coss.com use Amazon SES?
- Yes. coss.com delivers live email through Amazon SES, with one SES tenant per organization and per sub-account, and does suppressions, tracking, receiving, webhooks and logs itself.
- Why use coss.com instead of SES directly?
- To skip building what SES leaves to you: a dashboard, suppressions, tracking, contacts and broadcasts, stored inbound mail, signed webhooks, logs and sandbox environments. If you already run all of that, SES on its own costs less.
- Do I need to request production access like SES?
- No sandbox request. Sandbox environments work at sign-up, and live sending needs a verified email address, a live API key and a verified domain.
- Can coss.com receive email like SES receipt rules?
- Yes. coss.com receives at an environment address or your domain, stores each message and sends an email.received webhook, so there is no S3 bucket, SNS topic or Lambda function to set up.
Sources
Amazon SES's facts were checked on ; their pages are the final word on their prices and features.
The coss.com side
- Emailcoss.com Email is a transactional email API. Send single, batch and scheduled email from your domains, with templates, tracking and per-recipient webhooks.
- Marketing emailcoss.com Marketing email sends newsletters and announcements to your contacts as broadcasts, with audiences, segments, topics and a hosted preference center.
- Inbound emailcoss.com Inbound email receives mail at your domain or at an address coss.com gives each environment, and calls your webhook with every message, parsed.
- Email for platformscoss.com Email for platforms gives each of your users a sub-account with its own domains, sending reputation, quotas and suppression list, all on your API key.
Try coss.com next to Amazon SES.
A development key costs nothing and delivers nothing, so you can compare with real code.
Add coss.com to this project: read https://coss.com/llms.txt, get a development key with `npx coss-cli init --agents`, and build and test with it.