How to Send Emails with Flask Using Python | Flask Mail Tutorial (2025)

Want to send **emails from your Flask app** using Python? 📧 In this tutorial, I’ll show you **how to set up Flask-Mail** to send emails with Gmail SMTP, Outlook, or any custom mail server. Whether you're building a **contact form, password reset system, or notification emails**, this guide has you covered! 🚀

By the end of this video, you’ll know how to **configure Flask-Mail, send plain text and HTML emails, attach files, and use environment variables for security**.

---

## **🔹 What You’ll Learn in This Video:**
✅ How to install and set up **Flask-Mail**
✅ How to configure Flask to send **emails via SMTP**
✅ How to send **plain text and HTML emails**
✅ How to attach **files and images** to emails
✅ How to use **environment variables** for secure email credentials

---

## **🔹 Prerequisites**
✔️ **Flask Installed** (`pip install flask`)
✔️ **Basic Flask knowledge**
✔️ A **Gmail or any SMTP email account**

---

## **🔹 Step 1: Install Flask and Flask-Mail**
First, install the required packages:

```bash
pip install flask flask-mail
```

---

## **🔹 Step 2: Configure Flask-Mail**
Create a **Flask app** and set up the email configuration:

```python
from flask import Flask, render_template
from flask_mail import Mail, Message

app = Flask(__name__)

# Email Configuration

mail = Mail(app)

def send_email():
msg = Message(
"Hello from Flask",
)

try:
return "Email sent successfully!"
except Exception as e:
return str(e)

if __name__ == "__main__":
```

---

## **🔹 Step 3: Secure Your Credentials with Environment Variables**
⚠️ **Never store email credentials in your code**. Use environment variables instead:

1️⃣ Create a **`.env` file** in your project folder:

```
MAIL_PASSWORD=your_secure_password
```

2️⃣ Install **python-dotenv** to load environment variables:

```bash
pip install python-dotenv
```

3️⃣ Modify your code to use these variables:

```python
import os
from dotenv import load_dotenv

load_dotenv()

```

---

## **🔹 Step 4: Send HTML Emails**

---

## **🔹 Step 5: Attach Files to Emails**
You can also send **attachments (PDFs, images, etc.)**:

```python
```

---

## **🔹 Step 6: Send Emails via Outlook, Yahoo, or Custom SMTP**
Modify the **SMTP settings**:

🔹 **Gmail SMTP**
```
MAIL_PORT = 587
```

🔹 **Outlook SMTP**
```
MAIL_PORT = 587
```

🔹 **Yahoo SMTP**
```
MAIL_PORT = 465
MAIL_USE_SSL = True
```

🔹 **Custom SMTP Server**
Replace `MAIL_SERVER` and `MAIL_PORT` with your **email provider's SMTP settings**.

---

## **🔹 Common Issues & Fixes**
🔹 **SMTPAuthenticationError (535, ‘Incorrect password’)**
✅ **Fix:** Enable **App Passwords** in Gmail settings (Google may block less secure apps).

🔹 **smtplib.SMTPConnectError: (421, ‘Too many connections’)**
✅ **Fix:** Use a delay between emails or a mail queue like Celery.

🔹 **Email going to Spam?**
✅ **Fix:** Use a valid sender email and **avoid spammy keywords** in your subject line.

---

## **🔹 Who Is This Tutorial For?**
✅ Developers building **Flask apps that send emails**
✅ Anyone creating **contact forms, notifications, or authentication systems**
✅ Python beginners looking to learn **SMTP and Flask-Mail**

---

## **🔹 More Flask Tutorials:**
📌 **How to Build a Flask API** → [Watch Now]
📌 **How to Deploy a Flask App with Nginx & Gunicorn** → [Watch Now]
📌 **How to Connect Flask with MySQL** → [Watch Now]

---

## **👍 Like, Share & Subscribe!**
If this tutorial helped you, please **LIKE, SHARE, and SUBSCRIBE** for more **Flask and Python tutorials**! 🚀

💬 Have questions? Drop them in the **comments** below!

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### **🔹 Hashtags:**
#Flask #Python #FlaskMail #EmailAutomation #SMTP #PythonSMTP #FlaskTutorial #GmailSMTP #FlaskAPI

Now you can **send emails from your Flask app** like a pro! 🚀🔥

[LeDon-]

😩😩😩Why is it I'm seeing this channel now, I could have mastered python programming long time ago, & probably now hired as python developer to soon becoming a data analyst if not M/L engineer

Your tutorials are the best sir 👌🫡

[am.ahmedd]

مناشدة عاجلة لإنقاذ لإنقاذ أطفالي من الجوع اختكم ام سالم من فلسطين بيتي انهدم من الحرب و عايشة في خيمة ⛺️

‏An urgent appeal to save my children from hunger. Your sister Umm Salem from Palestine. My house.. has been destroyed by war and I am living in a tent ⛺️