Originally was going to do something like this but the logistics of maintaining a list that keeps growing would have made it a nightmare.
I had this planned… and now it is completed.
I have coped it over and anyone can modify the list.
If you dont have a Github account and don’t want to make one, just post here and I’ll add you to the wiki.
Progreso.pl (we are Polish web hosting company) - today launched full support for Let’s Encrypt in our control panel server (called Extranet). One click, 60 seconds and the site work in SSL version.
News about the implementation:
How to generate a certificate with one click:
https://pomoc.progreso.pl/baza_wiedzy/strony-www/ssl-https/#jak-wygenerowac-darmowy-certyfikat-lets-encrypt-w-extranecie
Thanks Let’s Encrypt!
Thanks, I have added you to the list. 
I am a GoDaddy customer. I contacted Support, and the agent had not heard of Let’s Encrypt. He checked, and confirmed that GoDaddy does not support it.
I have formally requested support for Let’s Encrypt, but bearing in mind that GoDaddy is a Tier 1 supplier of SSL certificates, I find it unlikely indeed that GoDaddy will agree.
Still, one can hope, seeing as Let’s Encrypt will not invalidate its primary SSL business, as GoDaddy sells only expensive certificates; people after cheap ones (even GoDaddy customers) will purchase them elsewhere.
They will not be motivated to do it right away, but once other major providers also start to support LE they will be forced to do it eventually.
While not yet officially supported, I can confirm the Let’s Encrypt tools work on Rackspace infrastructure (Load Balancers and Cloud Servers) with a handful of the support staff whom know how it works and use it successfully.
–…Archer
deep AG (switzerland) will support it from Jan/2016 for all Hosting products
https://www.configbox.com already supports free SSL with plesk lets encrypt plugin!
Added both to list. Thanks!
We are now fully supporting Lets Encrypt with a Cpanel Plugin on all our web hosting servers and services. Clients can generate a request a certificate for any or all domains or subdomains without restrictions on the number of certificates.
Implementation is done. Clients just have to inform support@deep.ch or give us a call to enable HTTPS.
Hi guys,
Love the idea of this thread - great to get a directory of services offering Let’s Encrypt.
I’m a co-founder at https://thisistap.com. Just a quick note to let you know that we’ve got the LE API integrated and are testing it over the weekend with a view to rolling it out next week for our pro sites as standard. Obviously SSL will be free to all users and we want to be transparent about our offering so please include us in the list. We’re also rolling out HTTP/2 support as we speak to support the LE SSL offering.
Thanks again,
Matt
Tap CCO
Hi everyone,
we at hostNET support LE since December '15 and after various tests with our customers, we have a final, nice howto for implementing and auto renew Let’s Encrypt in our Managed-Root Server Systems in some easy steps (see last link in german translation below)
Hallo,
wir von https://www.hostnet.de unterstützen LE seit der öffentlichen beta im Dezember 2015. Nach vielen erfolgreichen Tests mit unseren Kunden haben wir nun eine einfache How-To online, mit der man Let’s Encrypt auf unseren Managed-Root Serversystemen ganz einfach installieren und automatisch erneuern kann: https://www.hostnet.de/faq/wie-kann-ich-letsencrypt-nutzen.html
cheers,
Jimmy
Dreamhost’s integration has just been released to the public, seems pretty straight forward although it took a while for the cert to be copied out to their web servers.
Unfortunately, I couldn’t get Let’s Encrypt working with GoDaddy’s Shared Virtual Servers for the cPanel stuff, but you can get it working for your regular domain I do believe. It seems you just need to generate the certificate using a different machine, if I’m not mistaken. Seeing how I wanted to generate SSL certs for the cPanel stuff though, I needed to upgrade to a Private Virtual Server. I was then able to install the SSLs for the cPanel and WHM stuff, plus my domains.
Thanks! I have moved deep.ch to Supported list. 
@matttap Thanks for supporting Lets Encrypt! I have taken the time to add you to the list.
@Spork_Schivago You didn’t have to, you can generate the certs offsite via Linux live cd and just import then via SSL certs. There is a post about it with steps, its pretty simple. Bug them to support Let’s Encrypt so you don’t have to worry about it in future. Doubt they will care enough, but worth a try.
To everyone else, I have directly linked ALL sites which are supporting it. I have also VERIFIED ALL link proof and removed sites that shouldn’t be on the supported list.
Do not add useless sites to the list to promote your site, I will move you to trash list aka not supported and remove links. I check the wiki often. 
Hello
You can add http://buyshared.net to the list as well. We added LE support a couple weeks ago.
Francisco
We support Let’s Encrypt and currently have implemented LE certs for some of our customers as per here.
We’ve actually been testing Let’s Encrypt support ever since the beta started but it’s incredible the progress we’ve all made since the beta started.
hey @frantechca 
Thanks. I have added you to the list.
@KeiroD I have also added you to the list.
Thank you for supporting Let’s Encrypt!