A postdoc (short for postdoctoral researcher) is a temporary research position held by someone who has already earned a doctoral degree. It serves as an apprenticeship between finishing a PhD and launching a long-term career in academia, industry, or government research. Most postdocs last two to five years, and the role is almost entirely focused on research, with little to no teaching or administrative work required.
What a Postdoc Actually Does
The fundamental purpose of a postdoc is to deepen your research skills, either in the field you studied during your PhD or in a new one. You work under a faculty adviser (often called a principal investigator, or PI), contributing to their research program while building your own independent track record. The National Institute of Allergy and Infectious Diseases notes that postdocs are expected to have at least 75 percent of their time protected for research. The remaining time typically goes toward writing grant proposals, learning new techniques, mentoring graduate students, attending conferences, and publishing papers.
Publishing is central to the job. Postdocs are expected to produce lead-author publications, meaning papers where they are listed as the primary contributor. The quantity and quality of these publications largely determine a postdoc’s competitiveness for their next position, whether that’s a faculty role or a senior research job in industry.
Who Can Do a Postdoc
The baseline requirement is a completed doctoral degree, a PhD, MD, or equivalent. At many institutions, you don’t need to have the diploma in hand; an official letter confirming you’ve defended your dissertation and met all degree requirements is enough to start. Beyond the degree, there are often time limits. Washington University in St. Louis, for example, requires candidates to have fewer than four years of post-degree experience and enforces a five-year cap on total postdoctoral training. These limits reflect a broader norm: postdocs are meant to be transitional, not permanent.
How Long It Lasts
Most postdocs run between two and five years, though the length varies by field. In quantitative disciplines like biostatistics and bioinformatics, a majority of fellows complete their training in two years or less. In fields rooted in behavioral science or social science, longer appointments of more than two years are more common. Research from the National Institutes of Health’s training programs suggests that the ideal length of a postdoc for maximizing future research productivity differs by discipline, with some fields showing clear benefits from additional years of training and others showing none.
How Postdocs Are Paid
Postdoc salaries come from a few different funding streams. The most common is the adviser’s research grant: the PI uses federal or private funding to hire a postdoc as a temporary employee. Alternatively, postdocs can win their own individual fellowships, such as the NIH’s F32 award (a Kirschstein National Research Service Award), which pays the postdoc directly and is a strong credential on a CV. Institutional training grants (T32 programs) are a third route, where the university receives a block of funding to support multiple trainees.
The NIH sets widely referenced stipend levels that many universities use as a baseline. For fiscal year 2025, a first-year postdoc on an NIH fellowship earns $62,232 per year. That figure rises modestly with experience: $65,640 at year three, $70,344 at year five, and $75,564 at seven or more years. These numbers are stipends, not salaries in the traditional sense, and many postdocs at research universities earn in this range regardless of funding source. Compared to what PhD holders can earn in industry, particularly in fields like computer science or engineering, postdoc pay is notably low for the level of expertise involved.
Employee, Fellow, or Student?
One of the more confusing aspects of being a postdoc is figuring out what you actually are in the eyes of your institution. Postdocs whose salaries come from their adviser’s grant are generally classified as temporary employees, which means they pay standard income taxes and may receive benefits like health insurance and retirement contributions. Postdocs supported by their own fellowships are often classified as non-employee fellows, which can change their tax situation and benefit eligibility.
Some institutions take an entirely different approach. Stanford, for instance, classifies all postdocs as non-degree-seeking students regardless of funding source, which allows the university to offer a tailored benefits package including health care, dental care, disability insurance, and student loan deferment. At national laboratories managed by the University of California, postdocs are considered UC employees and receive corresponding benefits. At certain NIH campuses, postdocs are fellows rather than government employees. The practical takeaway: your benefits, tax withholding, and even loan deferment eligibility can vary dramatically depending on where you do your postdoc and how it’s funded.
Where Postdocs End Up
Many people enter a postdoc hoping it will lead to a tenure-track faculty position. The reality is that only about 17 percent of postdocs ultimately land one. The remaining 83 percent transition to careers outside the tenure track: industry research and development, government science, consulting, data science, science writing, patent law, and dozens of other paths. This isn’t a sign of failure. The academic job market has far more trained researchers than available faculty positions, and many postdocs discover that their skills are better compensated and more valued outside of academia.
That said, a postdoc remains effectively required for anyone pursuing a faculty career in the biological sciences, chemistry, physics, and most other bench sciences. In engineering and computer science, postdocs are less common because PhD graduates can move directly into well-paying industry or faculty roles. In the humanities and social sciences, postdoctoral fellowships exist but look different, often providing time and funding to turn a dissertation into a book rather than to run laboratory experiments.
Unionization and Changing Conditions
Postdoc working conditions have become a growing point of tension at universities across the United States. A wave of unionization efforts has pushed minimum salaries upward. At Princeton, collective bargaining between the university and the United Auto Workers union resulted in a proposal for postdoc minimum salaries to increase over 12 percent above the previous baseline of $65,000 over a three-year contract, with a first-year raise of just over 4.5 percent. Similar contracts have been negotiated at other major research universities. These agreements typically set a salary floor while allowing departments to pay above it based on field-specific market conditions and available funding.
How the Postdoc System Differs Internationally
The postdoc experience varies considerably across countries. The US system is known for its flexibility: contracts can be extended relatively easily, funding mechanisms are diverse, and postdocs frequently move between institutions. The UK operates similarly, with high researcher mobility and competitive grant systems. Continental Europe is more varied. France, for example, has historically had a high rate of “academic inbreeding,” with roughly 65 percent of researchers spending their entire careers at a single institution, compared to about 5 percent in Britain. This lack of mobility correlates with lower scientific productivity. Salaries for postdocs in some EU countries remain too low to support a reasonable standard of living, which drives many of Europe’s most promising early-career researchers to take postdoc positions in North America.