Quickstart: Send Your First Email

Send your first email with AhaSend by verifying a domain, creating a credential, and calling the REST API or connecting to the SMTP relay.

Before you start: You’ll need an AhaSend account. Sign up for free to get 1,000 emails per month at no cost.

Sign up for a free account
Verify your email address by clicking the link in your inbox
Log in to your dashboard to continue setup

Add & Configure Domain

Before you can send emails, you need to add and verify your domain:

Add your domain in your dashboard under Domains
Add the DNS records provided by AhaSend to your domain’s DNS settings
Wait for verification (usually takes a few minutes)

Need help with domain setup? Check out our detailed domain configuration guide for the required DNS records and links to DNS provider help.

Important: You cannot send emails until your domain is verified. The verification process ensures good deliverability and prevents spoofing.

Choose Sending Method

Decide how you want to send emails:

HTTP API

Recommended for most applications

Faster and more reliable
Better error handling
Rich metadata support

SMTP Relay

Use with existing email libraries

Works with any SMTP-compatible library
Easy migration from other providers
Supports all programming languages

Create Sending Credentials

Create the appropriate credentials for your chosen method:For HTTP API:

Go to Credentials → Add in your dashboard and choose API Key v2 for a send-only key (or use a full API v2 key with a send scope from Account Settings → API Keys)
Click “Create API Key”
Copy and securely store your API key

For SMTP:

Go to SMTP Credentials in your dashboard
Click “Create SMTP Credential”
Save the username and password

Keep your credentials secure! Never commit them to version control or expose them in client-side code.

Send & Verify First Email

Send your first email using the code examples below, then verify delivery:After sending:

Check your inbox - Your test email should arrive within seconds
Check the Messages page in your dashboard to see delivery status
Look for a 202 response with a message ID

Success! See your email in both your inbox and the Messages page? You’re all set up! 🎉

Jump to: HTTP API | SMTP Relay

Official SDKs

Node.js and TypeScript SDK

Install @ahasend/sdk, send a sandbox email and handle each recipient result.

Go SDK

Install ahasend-go, send a sandbox email and verify webhook signatures.

Choose a framework or platform guide for the full integration, or use the CLI quickstart to send from your terminal.

How Do I Send Through the HTTP API?

Call POST https://api.ahasend.com/v2/accounts/{account_id}/messages with your API key and a sender on your verified domain. See API authentication for the header and sending limits before adding recipients.

API Version Note: These examples use our latest API v2, which provides the most powerful features including advanced tracking, bulk sending, and better error handling. Existing v1 integrations can use the legacy API v1 reference; use v2 for new integrations.

Basic Email

curl -X POST https://api.ahasend.com/v2/accounts/{account_id}/messages \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{
    "from": {
      "name": "My App",
      "email": "hello@yourdomain.com"
    },
    "recipients": [
      {
        "name": "John Doe",
        "email": "john@example.com"
      }
    ],
    "subject": "Welcome to My App!",
    "text_content": "Thanks for signing up. We'\''re excited to have you!",
    "html_content": "<h1>Welcome!</h1><p>Thanks for signing up. We'\''re <strong>excited</strong> to have you!</p>"
  }'

const axios = require('axios');

const sendEmail = async () => {
  try {
    const email = {
      from: {
        name: 'My App',
        email: 'hello@yourdomain.com'
      },
      recipients: [
        {
          name: 'John Doe',
          email: 'john@example.com'
        }
      ],
      subject: 'Welcome to My App!',
      text_content: 'Thanks for signing up. We\'re excited to have you!',
      html_content: '<h1>Welcome!</h1><p>Thanks for signing up. We\'re <strong>excited</strong> to have you!</p>'
    };

    const response = await axios.post('https://api.ahasend.com/v2/accounts/{account_id}/messages', email, {
      headers: {
        'Content-Type': 'application/json',
        'Authorization': 'Bearer YOUR_API_KEY'
      }
    });

    console.log('Email sent:', response.data);
  } catch (error) {
    console.error('Error:', error.response.data);
  }
};

sendEmail();

import requests

def send_email():
    url = 'https://api.ahasend.com/v2/accounts/{account_id}/messages'
    headers = {
        'Content-Type': 'application/json',
        'Authorization': 'Bearer YOUR_API_KEY'
    }
    email = {
        'from': {
            'name': 'My App',
            'email': 'hello@yourdomain.com'
        },
        'recipients': [
            {
                'name': 'John Doe',
                'email': 'john@example.com'
            }
        ],
        'subject': 'Welcome to My App!',
        'text_content': 'Thanks for signing up. We\'re excited to have you!',
        'html_content': '<h1>Welcome!</h1><p>Thanks for signing up. We\'re <strong>excited</strong> to have you!</p>'
    }

    response = requests.post(url, json=email, headers=headers)

    if response.status_code == 202:
        print('Email sent:', response.json())
    else:
        print('Error:', response.json())

send_email()

<?php
$email = [
    'sandbox' => true,
    'from' => [
        'name' => 'My App',
        'email' => 'hello@yourdomain.com'
    ],
    'recipients' => [
        [
            'name' => 'John Doe',
            'email' => 'john@example.com'
        ]
    ],
    'subject' => 'Welcome to My App!',
    'text_content' => 'Thanks for signing up. We\'re excited to have you!',
    'html_content' => '<h1>Welcome!</h1><p>Thanks for signing up. We\'re <strong>excited</strong> to have you!</p>'
];

$options = [
    'http' => [
        'header' => "Content-type: application/json\r\nAuthorization: Bearer YOUR_API_KEY",
        'method' => 'POST',
        'content' => json_encode($email)
    ]
];

$context = stream_context_create($options);
$response = file_get_contents('https://api.ahasend.com/v2/accounts/{account_id}/messages', false, $context);

echo $response;
?>

package main

import (
    "bytes"
    "encoding/json"
    "fmt"
    "net/http"
)

type Email struct {
    From        Contact   `json:"from"`
    Recipients  []Contact `json:"recipients"`
    Subject     string    `json:"subject"`
    TextContent string    `json:"text_content"`
    HTMLContent string    `json:"html_content"`
}

type Contact struct {
    Name  string `json:"name"`
    Email string `json:"email"`
}

func main() {
    email := Email{
        From: Contact{
            Name:  "My App",
            Email: "hello@yourdomain.com",
        },
        Recipients: []Contact{
            {
                Name:  "John Doe",
                Email: "john@example.com",
            },
        },
        Subject:     "Welcome to My App!",
        TextContent: "Thanks for signing up. We're excited to have you!",
        HTMLContent: "<h1>Welcome!</h1><p>Thanks for signing up. We're <strong>excited</strong> to have you!</p>",
    }

    jsonData, _ := json.Marshal(email)

    req, _ := http.NewRequest("POST", "https://api.ahasend.com/v2/accounts/{account_id}/messages", bytes.NewBuffer(jsonData))
    req.Header.Set("Content-Type", "application/json")
    req.Header.Set("Authorization", "Bearer YOUR_API_KEY")

    client := &http.Client{}
    resp, err := client.Do(req)
    if err != nil {
        fmt.Println("Error:", err)
        return
    }
    defer resp.Body.Close()

    fmt.Println("Response Status:", resp.Status)
}

Replace the placeholders:

YOUR_API_KEY with your actual API key from Step 4
{account_id} with your account ID from your dashboard
hello@yourdomain.com with your verified domain from Step 2
john@example.com with the recipient’s email address

How Do I Send Through SMTP?

Use our SMTP servers with any email library. Great for existing applications or when you need SMTP compatibility.

SMTP Settings

Host: send.ahasend.com
Ports: 25, 587, 2525 (all support STARTTLS)
Authentication: Required
Username: Your SMTP username (from dashboard)
Password: Your SMTP password (from dashboard)

Get SMTP credentials: You should have created these in Step 4. If not, go to your dashboard → Credentials → Create New Credential

SMTP Examples

const nodemailer = require('nodemailer');

const transporter = nodemailer.createTransport({
  host: 'send.ahasend.com',
  port: 587,
  secure: false,
  auth: {
    user: 'YOUR_SMTP_USERNAME',
    pass: 'YOUR_SMTP_PASSWORD'
  }
});

const mailOptions = {
  from: '"My App" <hello@yourdomain.com>',
  to: 'john@example.com',
  subject: 'Welcome to My App!',
  text: 'Thanks for signing up. We\'re excited to have you!',
  html: '<h1>Welcome!</h1><p>Thanks for signing up. We\'re <strong>excited</strong> to have you!</p>'
};

transporter.sendMail(mailOptions, (error, info) => {
  if (error) {
    console.error('Error:', error);
  } else {
    console.log('Email sent:', info.response);
  }
});

import smtplib
from email.mime.text import MIMEText
from email.mime.multipart import MIMEMultipart

# Create message
msg = MIMEMultipart('alternative')
msg['Subject'] = 'Welcome to My App!'
msg['From'] = 'My App <hello@yourdomain.com>'
msg['To'] = 'john@example.com'

# Create text and HTML parts
text = "Thanks for signing up. We're excited to have you!"
html = "<h1>Welcome!</h1><p>Thanks for signing up. We're <strong>excited</strong> to have you!</p>"

msg.attach(MIMEText(text, 'plain'))
msg.attach(MIMEText(html, 'html'))

# Send email
try:
    server = smtplib.SMTP('send.ahasend.com', 587)
    server.starttls()
    server.login('YOUR_SMTP_USERNAME', 'YOUR_SMTP_PASSWORD')
    server.send_message(msg)
    server.quit()
    print('Email sent successfully!')
except Exception as e:
    print(f'Error: {e}')

<?php
use PHPMailer\PHPMailer\PHPMailer;
use PHPMailer\PHPMailer\SMTP;

require 'vendor/autoload.php';

$mail = new PHPMailer(true);

try {
    // Server settings
    $mail->isSMTP();
    $mail->Host       = 'send.ahasend.com';
    $mail->SMTPAuth   = true;
    $mail->Username   = 'YOUR_SMTP_USERNAME';
    $mail->Password   = 'YOUR_SMTP_PASSWORD';
    $mail->SMTPSecure = PHPMailer::ENCRYPTION_STARTTLS;
    $mail->Port       = 587;

    // Recipients
    $mail->setFrom('hello@yourdomain.com', 'My App');
    $mail->addAddress('john@example.com', 'John Doe');

    // Content
    $mail->isHTML(true);
    $mail->Subject = 'Welcome to My App!';
    $mail->Body    = '<h1>Welcome!</h1><p>Thanks for signing up. We\'re <strong>excited</strong> to have you!</p>';
    $mail->AltBody = 'Thanks for signing up. We\'re excited to have you!';

    $mail->send();
    echo 'Email sent successfully!';
} catch (Exception $e) {
    echo "Error: {$mail->ErrorInfo}";
}
?>

package main

import (
    "gopkg.in/gomail.v2"
    "log"
)

func main() {
    m := gomail.NewMessage()
    m.SetHeader("From", "hello@yourdomain.com")
    m.SetHeader("To", "john@example.com")
    m.SetHeader("Subject", "Welcome to My App!")
    m.SetBody("text/plain", "Thanks for signing up. We're excited to have you!")
    m.AddAlternative("text/html", "<h1>Welcome!</h1><p>Thanks for signing up. We're <strong>excited</strong> to have you!</p>")

    d := gomail.NewDialer("send.ahasend.com", 587, "YOUR_SMTP_USERNAME", "YOUR_SMTP_PASSWORD")

    if err := d.DialAndSend(m); err != nil {
        log.Fatal(err)
    }

    log.Println("Email sent successfully!")
}

Next Steps

Now that you’ve sent your first email, here’s what to do next:

Set up Domains

Add and verify domains for better deliverability and custom from addresses

Send with SMTP

Use SMTP credentials to send emails through your existing email libraries

Send with API

Advanced API features like templates, attachments, and bulk sending

Sandbox SMTP

Test safely with sandbox mode to avoid sending emails to real recipients

Why Did My First Send Fail?

Having issues? Here are the most common problems:

401 Unauthorized Error

Check that your API key is correct and properly formatted
Make sure you’re using the Authorization: Bearer header format
Verify your API key has the correct scopes in your dashboard

Domain Still Not Verified

Most records verify within minutes. DNS changes can take up to 48 hours to propagate.
Double-check that you added all required DNS records exactly as shown
Use a DNS checker tool to verify your records are live
Contact support if verification fails after 48 hours

SMTP Authentication Failed

Double-check your SMTP username and password
Make sure you created SMTP credentials in your dashboard (not your login password)
Try port 2525 if 587 is blocked by your network

Email Not Delivered

Check your dashboard message logs for delivery status
Verify the recipient email address is correct
Check the recipient’s spam folder
Make sure you’re not hitting monthly allowance (the Free plan includes 1,000 emails/month); see API rate limits for request limits

Need more help? Email our engineering team at support@ahasend.com - we typically respond within a few hours!

Domain, Delivery and Migration Guides

DNS provider guides: record names and setup steps for Cloudflare, GoDaddy, Namecheap, Route 53, Hetzner, IONOS, STRATO, TransIP, OVHcloud, Squarespace and Vercel.
SPF, DKIM and DMARC: what each check proves and how domain alignment works.
Bounces and suppressions and SMTP error codes: understand a failed send and choose the next step.
Deliverability best practices: sender reputation, warm-up, sending subdomains, Gmail and Yahoo requirements, and one-click unsubscribe.
Migrate from SendGrid, Mailgun, Postmark, Resend or Amazon SES, including suppression imports.
Troubleshooting and FAQ: domain checks, missing messages, port 465, permission errors and blocked recipients.
Email glossary and credential security: definitions and practical steps to protect your account.

Getting Started

Domain Authentication

Delivery and Troubleshooting

Sending with SMTP

Sending with the API

Email Tracking

Integrations

Data Retention

Security

Scaling up

Quickstart: Send Your First Email

HTTP API

SMTP Relay

Official SDKs

Node.js and TypeScript SDK

Go SDK

How Do I Send Through the HTTP API?

Basic Email

How Do I Send Through SMTP?

SMTP Settings

SMTP Examples

Next Steps

Set up Domains

Send with SMTP

Send with API

Sandbox SMTP

Why Did My First Send Fail?

Domain, Delivery and Migration Guides

HTTP API

SMTP Relay

​Official SDKs

Node.js and TypeScript SDK

Go SDK

​How Do I Send Through the HTTP API?

​Basic Email

​How Do I Send Through SMTP?

​SMTP Settings

​SMTP Examples

​Next Steps

Set up Domains

Send with SMTP

Send with API

Sandbox SMTP

​Why Did My First Send Fail?

​Domain, Delivery and Migration Guides

​Related Guides

Official SDKs

How Do I Send Through the HTTP API?

Basic Email

How Do I Send Through SMTP?

SMTP Settings

SMTP Examples

Next Steps

Why Did My First Send Fail?

Domain, Delivery and Migration Guides

Related Guides