How to Add SSL to Your Internal Intranet 4 options for secure HTTPS access inside your network.
★ Adding SSL isn't difficult. Let's SimplifyIT ★
Even if your intranet never leaves your internal network, securing it with HTTPS is a smart move - especially if you're handling sensitive data or facing compliance requirements.
Below are four ways to add SSL to your internal intranet site, depending on your setup.
This is the easiest and cheapest option (it's free), but it comes with browser warnings unless you manually trust the certificate (which you can achieve via GPO).
- Free and fast to set up
- May require changes to GPO for browsers
- May require user training to bypass warnings
If your internal intranet uses an internal domain that matches your external one (like *.simplifyit.com), you may be able to use a wildcard certificate from a trusted authority.
- Works without browser warnings
- Requires internal DNS to match public domain
- Mid-range cost depending on provider - but you may already have one (so free)
If you want to purchase a standalone SSL certificate (not a wildcard), it's easiest when your internal domain uses a standard ending (.net, .com, .org, etc.). Some certificate authorities will secure intranet URLs that aren't publicly reachable, but this often requires extra validation steps and may cost more.
- Great for real internal hostnames or IPs
- Trusted by browsers out of the box
- More expensive than standard SSL - unless your domain name matches your external domain
Some organizations run their own internal CA, allowing them to issue certificates for intranet sites without outside involvement. It requires more setup but avoids ongoing fees.
- Push trusted root certs via group policy
- Zero per-certificate cost after setup
- Best for institutions with IT staff or domain expertise
And don't forget to redirect to HTTPS in IIS after installation.
Common Questions
How to install an internal SSL certificate?
Install it like you would on a public site: create a CSR, sign it with an internal or external CA, and install the certificate on your web server. Our full guide covers step-by-step instructions.
Are self-signed certificates secure for internal use?
They're fine for testing or small, low-risk internal sites, but they lack a trusted chain and won't pass compliance audits. Users also have to manually trust them, which can be a hassle.
How to add a self-signed SSL certificate?
Generate the certificate, install it on the server, and manually trust it on each client device. It's quick but usually triggers browser warnings unless every machine trusts your root cert.
Is SSL required for intranet applications?
It's strongly recommended. SSL encrypts credentials and data in transit, helps prevent man-in-the-middle attacks, and supports audit compliance.
Does an internal intranet really need SSL?
Yes. Even if your intranet is only accessible inside your network, adding SSL protects login credentials, prevents man-in-the-middle attacks, and helps with audit compliance.
Can I use a free SSL certificate for my internal intranet?
You can use a self-signed certificate, but it will trigger browser warnings unless users manually trust it. For teams that don't mind the warnings, it's a fast and free option.
What's the easiest way to secure an internal site without warnings?
Using a wildcard certificate for your internal domain is usually the simplest path. It avoids browser errors and can be reused across internal subdomains - assuming your internal DNS mirrors a real domain.
What if our intranet doesn't use a public-facing domain?
You can either run your own internal certificate authority (CA) or look into specialized public certs for internal hostnames. Both options require more effort but eliminate browser warnings.
Is running an internal certificate authority (CA) worth it?
It depends on your team. For larger organizations or those with existing group policy infrastructure, setting up a CA can eliminate certificate costs and provide complete control.
