SSL for E-Commerce Websites: What You Need and How to Set It Up

Introduction

An online store asks customers for exactly the details attackers want: passwords, addresses, and card numbers. HTTPS, the secure version of the web, is what keeps that information from being read or changed on its way to your server. Browsers also warn visitors about sites that lack it, so it is the minimum a store needs before it takes its first order.

This guide covers what HTTPS does for a store, what it doesn’t do, how it relates to PCI DSS, which certificate to choose, how to set it up, and how to keep it working. If you are new to the topic, start with our guide, How SSL/TLS Certificates Protect Customer Data.

What HTTPS Protects in an Online Store

An SSL/TLS certificate lets the browser and your server agree on encryption keys before any page content is sent. Cloudflare’s explanation covers the handshake in detail. For a store, the practical result is that what customers type and what your server sends back is scrambled for anyone watching the connection.

The rule is simple: every page on your store should load over HTTPS, not only checkout. A mixed approach, where only some pages are encrypted, leaves cookies and logins exposed and triggers browser warnings.

HTTPS also helps customers confirm they have reached your real domain, because the certificate is tied to it. It cannot tell them whether you are a trustworthy business. The FTC points out that data may be encrypted on its way to a site and still not be safe from scammers running it, so a padlock only proves the connection is encrypted.

SSL/TLS and PCI DSS: What a Certificate Does Not Cover

PCI DSS is the security standard for payment card data, managed by the PCI Security Standards Council. According to the Council’s guide, it applies to any organization that stores, processes, or transmits cardholder data, and card brands and acquiring banks set how each merchant must validate compliance.

Two points matter for store owners:

1. Encryption in transit is one requirement among many. PCI DSS requires strong cryptography and security protocols to protect card data sent over public networks. The Council’s FAQ on requirement 4.2 adds that this includes supporting only secure protocol versions and configurations. A certificate on its own does not make a store compliant.
2. Old protocols no longer count. The Council’s migration guide says SSL and early TLS are no longer considered secure for payment card data and recommends TLS 1.2 or higher, with fallback to the older versions disabled. So the “SSL” in “SSL certificate” is a name, not a protocol you should be running.

Cut Down Your Scope

The more card data touches your own server, the more of PCI DSS applies to you. Many small stores reduce that by sending customers to a hosted payment page or embedding a payment provider’s fields, so card numbers never pass through the store’s own systems. Ask your payment provider which integration keeps card data off your server, and confirm with your acquiring bank what you need to validate.

Other Things a Certificate Doesn’t Protect

• Customer data stored in your database or backups
• A compromised plugin, theme, or admin account
• Phishing sites that imitate your store
• Traffic that a CDN or load balancer decrypts before it reaches your server, unless the connection after that point is also encrypted

The next sections cover choosing and installing a certificate. After that, the “Beyond SSL” section lists the other basics every store needs.

Which Certificate Should Your Store Use?

All certificate types give the same level of encryption. Cloudflare notes that the difference is how much the authority verified about you, and how many domains the certificate covers. Pick by your setup:

Two cautions apply to EV. It does not give customers extra visible reassurance: Chrome 77 stopped showing the company name in the address bar in September 2019, and there is no longer a green bar. And it doesn’t make your checkout more secure. For most stores, a DV or OV certificate that renews automatically is the better investment.

If you use a hosted store platform or a CDN, check whether it already provides a certificate for your domain before you buy another. Compare certificate options on the AvenaCloud SSL page.

How to Set Up HTTPS on Your Store

The exact clicks depend on your platform and host, but the steps are the same.

1. Check what you already have. Some hosts and store platforms provide a certificate or a free one automatically. If so, enable it instead of buying another.
2. Pick the certificate type using the table above.
3. Generate a private key and a certificate signing request (CSR) on your server. Keep the private key secret: never email it, never put it in a public folder or code repository.
4. Prove you control the domain. The authority will ask you to add a DNS record, publish a file, or confirm by email. Free authorities such as Let’s Encrypt automate this with software on your server.
5. Install the certificate with its full chain. Include the intermediate certificates the authority gives you, or some browsers and payment integrations will show trust errors.
6. Allow only modern protocols. Configure the server for TLS 1.2 and TLS 1.3, and disable SSL and early TLS, in line with the PCI Council’s guidance.
7. Redirect all HTTP traffic to HTTPS with a permanent redirect, and update the store address in your platform settings.
8. Update everything that points at your site. This includes canonical tags, your sitemap, payment gateway return URLs, analytics, and ad links. Add the HTTPS version of the site to Search Console.
9. Fix mixed content (see the next section).
10. Mark cookies as secure so that session and cart cookies are only sent over HTTPS.
11. Turn on HSTS once everything works. This header tells browsers to use only HTTPS for your site. Test first, because it is hard to undo quickly.
12. Test it. Place a test order, open the store in several browsers and on a phone, check the certificate details, and run an online SSL/TLS test such as Qualys SSL Labs.

If you run your store on your own server, a VPS gives you control of the web server configuration these steps need.

Keeping HTTPS Working

Setting up HTTPS is a one-time job. Keeping it working is a routine one, and the failures show up exactly where customers pay.

Renewal Is Getting More Frequent

The old advice that certificates last one to two years is out of date. The CA/Browser Forum approved a schedule that, as Sectigo summarizes, caps publicly trusted certificates at:

Manual renewal will not keep up with that. Use automated issuance wherever you can, such as software that speaks the ACME protocol, set expiry alerts that reach a named person, and keep a simple list of every certificate your store uses, including subdomains and payment or API endpoints.

Mixed Content

Mixed content means an HTTPS page that still loads an image, script, font, or stylesheet over plain HTTP. Browsers may block those items or show a warning, and a blocked script can break a cart or checkout button. To fix it, open your browser’s developer tools and look for mixed-content warnings, change hard-coded http:// links to https://, and check theme files, product descriptions, and third-party widgets. A Content-Security-Policy: upgrade-insecure-requests header can help as a safety net, but it is better to correct the links themselves.

Common Problems and Quick Checks

If you think your private key was exposed, treat it as compromised: create a new key pair, get a new certificate, install it, and ask your authority to revoke the old one.

Beyond SSL: Other Store Security Basics

HTTPS protects data on the move. These steps protect everything else.

• Turn on multifactor authentication for every admin and staff account. CISA says it usually stops an attacker who has stolen a password, and it recommends phishing-resistant options such as passkeys or security keys where possible.
• Use long, unique passwords in a password manager. NIST suggests at least 15 characters, no reuse, and changing a password when it appears in a breach.
• Keep the platform, plugins, themes, and server up to date. Outdated or abandoned components are a common way in.
• Keep card data off your server by using your payment provider’s hosted page or fields.
• Back up the store and test a restore, with copies kept away from the server.
• Prepare for traffic floods. A DDoS attack uses a network of infected devices to overwhelm a site so real customers can’t get through, which is costly in the middle of a sale. Hosting with built-in filtering, such as AvenaCloud’s DDoS-protected dedicated servers, or a proxy in front of your store can help.
• Limit access to the server itself. Use SSH keys, a firewall, and only the ports you need. Our guide on securing your IP address from hackers walks through the steps.
• Watch for phishing aimed at you and your customers. A padlock on a fake store proves nothing, so train staff to check links before logging in.

Frequently Asked Questions

Does my online store need an SSL certificate?

Yes. Any store that has logins, carts, or payment forms should load every page over HTTPS. Browsers warn visitors about sites that don’t, and payment standards expect card data to be protected in transit.

Does an SSL certificate make my store PCI compliant?

No. PCI DSS requires strong cryptography and secure protocol versions for card data in transit, and it also covers many other areas, such as how you store and handle data. A certificate helps with one requirement. Confirm your obligations with your payment provider and acquiring bank.

Is SSL the same as TLS?

SSL is the older name and TLS is the protocol in use today. The PCI Council says SSL and early TLS are no longer secure for payment card data and recommends TLS 1.2 or higher, so make sure your server uses a modern version.

Which certificate is best for an online store?

A domain-validated (DV) certificate that renews automatically is enough for most stores. Choose a wildcard if you use several subdomains, a multi-domain certificate for several brands, and OV or EV only if you want your organization verified in the certificate. All types encrypt equally.

Can I use a free certificate for my store?

Yes, if it is issued by a trusted authority, such as Let’s Encrypt, and installed properly. The encryption is the same. Make sure renewal is automated and that your host or platform supports it.

How long does a certificate last?

Publicly trusted certificates are limited to 200 days from March 15, 2026, dropping to 100 days in March 2027 and 47 days in March 2029. Plan on automated renewal.

What happens if my certificate expires?

Browsers show a full-page security warning, and customers may be unable or unwilling to check out until you renew.

Does HTTPS improve my store’s SEO?

Slightly. Google has treated HTTPS as a ranking signal since 2014, but a certificate alone won’t lift your pages. Customer trust and checkout reliability are better reasons to use it.

Conclusion

For an online store, HTTPS is the baseline: it protects logins, carts, and card details on the way to your server, and it keeps browsers from warning customers away. It is not a compliance badge or a full security plan. Choose a certificate that fits your setup, allow only modern TLS versions, fix mixed content, redirect everything to HTTPS, and automate renewal so a lapsed certificate never stops a sale.

Ready to set it up? See AvenaCloud’s SSL certificates, host your store on a VPS, or visit the AvenaCloud home page. If you are migrating a store to HTTPS and want help with redirects, site speed, or technical SEO, KowsarStudio offers SEO audits and web development.