Create a SendGrid account

SendGrid is a strong choice when clients want a managed ESP with a simple API, built-in stats, and no AWS console. EonMailer connects via API key — you still authenticate the client’s domain in DNS.

When agencies pick SendGrid

• Client already pays for SendGrid elsewhere and wants to migrate lists without changing infrastructure.
• Team prefers Twilio/SendGrid support over IAM policies.
• Volume fits SendGrid plan tiers (evaluate vs SES per-thousand math on Pricing).

Step 1 — Sign up

1. Go to https://signup.sendgrid.com/ (or Twilio SendGrid portal if your agency has a parent account).
2. Use a shared agency ops email or client-specific mailbox (sendgrid-acme@agency.com).
3. Complete profile: company name, role, expected email volume (honest estimates help Twilio fraud checks).
4. Verify your signup email immediately — unverified accounts can’t send.

Step 2 — Complete account authentication

Twilio may require:

1. Phone verification
2. Business details for higher volume
3. Acknowledgement of anti-spam policies

Warning SendGrid suspends accounts with sudden spam spikes or purchased lists. Document opt-in source before first large import in EonMailer.

Step 3 — Choose a plan

For agency client work:

• Essentials or Pro tiers are typical — compare monthly email caps vs overage.
• Avoid tying multiple unrelated clients to one SendGrid subuser without isolation — prefer subusers per client (SendGrid Pro feature) or separate accounts.

Note whether your plan includes dedicated IP (usually not needed at launch; shared pools are fine during warmup).

Step 4 — Verify a single sender (bootstrap)

Before domain authentication, SendGrid often requires a Single Sender Verification:

1. Settings → Sender Authentication → Verify a Single Sender.
2. Enter From name, address (you@client.com), reply-to, company address.
3. Click the verification link sent to that inbox.

This unblocks limited testing but is not production-ready — you still need domain authentication for SPF/DKIM alignment.

Step 5 — Create a subuser (optional, recommended)

If your SendGrid plan supports subusers:

1. Settings → Subuser Management → Create subuser.
2. Name: client-acme.
3. Assign API keys per subuser later so Acme keys can’t send as another client.

EonMailer stores one API key per workspace — map one subuser ↔ one EonMailer client.

Step 6 — Document account details

Field	Value
Login email
Plan tier
Subuser name
Single sender verified	Yes/No
Domain auth status	Pending

Next steps

1. Create a SendGrid API key with Mail Send scope only.
2. Connect SendGrid to EonMailer.
3. Complete Domain authentication in SendGrid and verify in EonMailer.