SendGrid
The most popular transactional email service, owned by Twilio.
Overview
SendGrid is the industry-leading email delivery platform, trusted by over 80,000 companies including Uber, Spotify, and Airbnb. Owned by Twilio since 2019, SendGrid offers exceptional deliverability rates, comprehensive analytics, and a generous free tier that makes it perfect for WordPress sites of all sizes.
With Authority Mailer SMTP, connecting SendGrid to WordPress takes just 3 minutes. You'll get instant access to SendGrid's world-class infrastructure without writing a single line of code.
SendGrid Features
Requirements
Before you start, make sure you have:
- 1SendGrid account (free tier available)
- 2API Key with "Mail Send" permission
- 3Verified sender identity (email or domain)
Step-by-Step Setup Guide
Create a SendGrid Account
1. Go to sendgrid.com and click "Start for Free"
2. Enter your email address and create a password
3. Complete the account verification process
4. Answer the setup questions (you can skip marketing setup)
Verify Your Sender Identity
SendGrid requires sender verification to prevent spam:
Option A: Single Sender Verification (Easiest)
1. Go to Settings → Sender Authentication
2. Click "Verify a Single Sender"
3. Enter your sender details (name, email, address)
4. Check your email and click the verification link
Option B: Domain Authentication (Recommended for Production)
1. Go to Settings → Sender Authentication → Authenticate Your Domain
2. Enter your domain name
3. Add the provided DNS records to your domain
4. Click "Verify" once DNS propagates
Create an API Key
1. Go to Settings → API Keys
2. Click "Create API Key"
3. Name it "Authority Mailer SMTP" (or similar)
4. Select "Restricted Access"
5. Enable "Mail Send" → Full Access
6. Click "Create & View"
7. **Copy the API key immediately** - you won't see it again!
Configure Authority Mailer SMTP
1. In WordPress, go to Authority Mailer SMTP → Settings
2. Select "SendGrid" from the provider dropdown
3. Paste your API key in the "API Key" field
4. Set your "From Email" (must match verified sender)
5. Set your "From Name" (e.g., "Your Site Name")
6. Click "Save Settings"
7. Click "Send Test Email" to verify
💡 Pro Tips
- Use domain authentication instead of single sender for better deliverability
- Enable link and open tracking in SendGrid settings for engagement metrics
- Set up dedicated IP addresses for high-volume sending
- Use categories in Authority Mailer SMTP to segment email analytics
- Monitor your sender reputation score in SendGrid's dashboard
🔧 Troubleshooting
❓ Test email fails with "unauthorized" error
✅ Your API key is invalid or doesn't have Mail Send permission. Create a new API key with "Mail Send" access enabled.
❓ Emails not being delivered
✅ Check SendGrid's Activity Feed for delivery status. Common issues: sender not verified, recipient bounced, or content flagged as spam.
❓ From email address rejected
✅ The "From" email in Authority Mailer SMTP must match a verified sender in SendGrid. Either verify the email address or use domain authentication.
❓ Rate limited / hitting daily limit
✅ Free tier is limited to 100 emails/day. Upgrade to a paid plan or optimize your email sending (combine notifications, use digests).
Ready to Set Up SendGrid?
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