How to Send Emails in Python (2026 Guide)

Sending Emails from Python

Python has built-in email support via smtplib, but using a REST API is simpler and more reliable for production applications.

Method 1: REST API with requests

import requests

response = requests.post(
    "https://api.unosend.co/v1/emails",
    headers={
        "Authorization": "Bearer un_your_api_key",
        "Content-Type": "application/json",
    },
    json={
        "from": "hello@yourdomain.com",
        "to": "user@example.com",
        "subject": "Hello from Python!",
        "html": "<h1>Welcome!</h1><p>Sent from Python.</p>",
    },
)

print(response.json())

Method 2: Using the Unosend Python SDK

pip install unosend

from unosend import Unosend

client = Unosend(api_key="un_your_api_key")

result = client.emails.send({
    "from": "hello@yourdomain.com",
    "to": "user@example.com",
    "subject": "Welcome!",
    "html": "<h1>Hello!</h1>",
})

print(f"Email sent: {result['id']}")

Django Integration

# settings.py
UNOSEND_API_KEY = os.environ.get("UNOSEND_API_KEY")

# views.py
from unosend import Unosend
from django.conf import settings

unosend = Unosend(api_key=settings.UNOSEND_API_KEY)

def send_welcome_email(user):
    unosend.emails.send({
        "from": "welcome@yourapp.com",
        "to": user.email,
        "subject": f"Welcome, {user.first_name}!",
        "html": f"<h1>Welcome to our app, {user.first_name}!</h1>",
    })

Flask Example

from flask import Flask, request, jsonify
from unosend import Unosend

app = Flask(__name__)
unosend = Unosend(api_key=os.environ["UNOSEND_API_KEY"])

@app.route("/api/contact", methods=["POST"])
def contact():
    data = request.json
    result = unosend.emails.send({
        "from": "contact@yourapp.com",
        "to": "team@yourapp.com",
        "subject": f"Contact: {data['name']}",
        "html": f"<p>{data['message']}</p>",
    })
    return jsonify({"success": True, "id": result["id"]})

FastAPI Example

from fastapi import FastAPI
from pydantic import BaseModel
from unosend import Unosend

app = FastAPI()
unosend = Unosend(api_key=os.environ["UNOSEND_API_KEY"])

class ContactForm(BaseModel):
    name: str
    email: str
    message: str

@app.post("/api/contact")
async def contact(form: ContactForm):
    result = unosend.emails.send({
        "from": "contact@yourapp.com",
        "to": "team@yourapp.com",
        "subject": f"Contact: {form.name}",
        "html": f"<p>From: {form.name}</p><p>{form.message}</p>",
    })
    return {"success": True}

Production Tips

• Use environment variables — Never hardcode API keys
• Async sending — Use httpx or aiohttp for async Python apps
• Retry on failure — Use tenacity library for retry logic
• Validate emails first — Check email format before sending
• Track delivery — Set up webhooks for bounce and complaint handling