The ELLIS PhD program is a pan-European doctorate in machine learning where you are jointly supervised by two ELLIS researchers, usually at two institutions in two different countries, with a research stay abroad built into the degree. You apply once, through one central portal, and that single application can reach many supervisors at the same time, with a deadline that lands in November each year. It is genuinely competitive: a recent cycle drew more than 3,100 applicants for a small set of funded places, so plan for long odds and apply with intent.
What the ELLIS PhD program actually is
ELLIS stands for the European Laboratory for Learning and Intelligent Systems, a network of machine learning groups spread across Europe. The PhD program is the network's flagship doctoral track. Instead of applying to one lab in one country, you register on a shared portal that lists every advisor recruiting in the current round, then submit one application that names the supervisors you want to work with.
Two things make it distinct. First, every student gets a main advisor and a co-advisor at different institutions, so the PhD is built around collaboration across borders. Second, the whole intake runs on a single annual call, which keeps the process simple to enter but very crowded. According to the official ELLIS PhD admission page, one recent cycle attracted more than 3,100 interested candidates, and the number of places offered each year runs from a few dozen to around a hundred depending on funding. Treat those figures as illustrative, because they move every year.
How co-supervision and the exchange work
The two-supervisor model is the core of the program. Your main advisor is one of the recruiting ELLIS researchers you applied to. Your co-advisor is a second ELLIS member, fellow, or scholar based in Europe at an institution in a different country. You do not need the co-advisor locked in when you apply. That pairing can usually be settled in the months after you are accepted.
The exchange is not optional. On the academic track you spend a minimum of six months doing research at your co-advisor's institution abroad, which is why most ELLIS PhDs end up living in two countries over the course of the degree. There are also industry and interdisciplinary tracks with slightly different mobility rules.
One point that surprises applicants: ELLIS itself does not pay your salary. Funding and your PhD contract come from the host institution under its national rules, which across much of Europe means a salaried employment contract rather than a bursary. Pay, tax, and residence rights therefore depend heavily on which country your main advisor sits in. If that matters to you, our post on how AI PhD pay and stipends compare across Germany, Switzerland, and the Netherlands breaks down the differences.
What a strong application needs
Because one application competes against thousands, fit does most of the work. The strongest candidates are not the ones with the longest CV. They are the ones whose interests line up cleanly with a specific recruiting advisor. A few things carry real weight:
- Research fit. Name advisors whose recent papers you can actually talk about, and say what you would work on with them.
- Evidence of research ability. A publication, a strong thesis, or a serious project matters more than certificates. For machine learning, one solid piece of research beats a stack of coursework.
- Strong letters. Referees who can speak to your research potential, requested through the portal before the reference deadline.
- A clear statement. A focused research statement that connects your background to your chosen supervisors, not a generic personal essay.
How to apply: your before-November checklist
The mechanics are straightforward once you know the order. Here is what to do, starting well before the deadline:
- Open the current call on the ELLIS application portal (apply.ellis.eu) and read the list of advisors recruiting this round.
- Shortlist two to four advisors whose work genuinely overlaps with yours. Depth beats breadth here.
- Email each of them a short, specific note before the deadline: who you are, one or two ideas you would want to pursue, and why their group. Many advisors weigh prior contact, and a good exchange can shape whether they flag your file.
- Line up two to three referees early and request their letters through the portal, since referees submit on their own deadline after you ask them.
- Write one research statement tuned to your top choices, then register and submit before the November cut-off. Confirm the exact date on the official ELLIS pages, because it shifts slightly each year.
This is informational, not legal, immigration, tax, or financial advice, and deadlines and rules change, so verify the current call before you rely on any date here.
The honest takeaway
The ELLIS PhD is a strong fit if you are set on a research career, want to be in Europe, and value a salaried contract plus a built-in international collaboration. It suits people who already have a clear research direction and can point to a specific advisor. It is a poor fit if you need a fast or guaranteed answer, have not done the work to find a genuine research match, or are not ready to spend part of the degree abroad.
The catch worth planning around is that your pay and immigration path are set by the host country, not by ELLIS. Two students in the same program can have very different take-home pay and years-to-residence depending on where their advisor sits. That is a where-to-relocate question as much as an academic one, and it is exactly what the AI Relocation Guide is built to answer, so you can compare all 21 countries before you commit. If you are weighing external funding too, our guide to Marie Curie fellowships for AI researchers covers another well-funded European route.
Pick the advisor first and the country second, but never forget that in ELLIS the country you land in quietly decides your salary and your path to staying.
