Are Let's Encrypt TLS Certificates Really Free?
Yes. Let's Encrypt issues TLS certificates at no cost, and the site describes itself as "a nonprofit providing free TLS certificates to more than 700M websites." There is no paid tier described on the page, and no pricing, checkout, or payment flow appears in the site content. The free certificates are funded by donations and corporate sponsorship rather than by charging the people who use them.
What "free" actually covers
The certificate itself costs nothing. According to the site, Let's Encrypt is a Certificate Authority that provides free TLS certificates so websites can enable HTTPS encryption. It is a project of the nonprofit Internet Security Research Group (ISRG).
Two practical conditions come with that:
- You must prove control of the domain. The site states plainly: "In order to get a certificate for your website's domain, you have to demonstrate control over the domain." This is a technical requirement of the issuance process, not a fee.
- You need an ACME client to automate issuance and renewal. Let's Encrypt points users to a list of recommended ACME clients for automatically managing certificates.
So the cost is zero, but the work of setup and renewal is yours (or your client's) to automate.
Why it can stay free
The model is donation- and sponsor-funded, not ad- or fee-funded. The page's "Global impact made possible by generosity" section asks visitors to donate, saying contributions "help keep Let's Encrypt free and accessible to millions of websites around the world." A separate sponsorship path exists for companies that "rely on or value our work to encrypt the Web."
This matters if your real question is durability: the free service is tied to continued giving, and the site treats individual donations and company sponsorship as the mechanism that sustains it.
What the page does not say
Be careful not to read more into "free" than the source supports:
- No rate limits, certificate lifetimes, or per-domain quotas are stated on this page.
- No paid plans, premium support, or upsells are mentioned.
- No account, login, or payment requirement is described for obtaining a certificate.
If you need those specifics, they belong to the documentation and ACME client pages rather than the homepage.
If you want to use it
- Confirm you can demonstrate control over the domain you want a certificate for.
- Pick a recommended ACME client from the site's list to handle issuance and renewal automatically.
- Read the documentation for the issuance process and best practices.
- If you get stuck, the Let's Encrypt community forum is offered for technical assistance from experts, volunteers, and ISRG staff.
If you want to support it
- Individuals: use the Donate option; the site frames every contribution, large or small, as making a difference.
- Companies: explore the sponsorship program, which the site presents as the route for organizations that depend on or value encrypted web traffic.
Either way, the certificates you or others obtain remain free — the giving is what keeps that true.