It’s a natural question to ask when applying to a PhD program: “Do I need to already have publications before I apply?”. Simply put the answer is no, you do not need to have published papers to apply to a PhD. Having said that though, I do think there are clear advantages of having some publication experience in helping your application stand out from other candidates.
When entering into PhD research, you’re entering into an environment that’s built on a framework of disseminating new findings and making an original contribution to knowledge in your field. Key to this is the ability to write papers that stand up to peer-review and get published in the journals relevant to your research area. So, you can see why, as an applicant, being able to demonstrate real evidence of being able to do this through previously published papers is going to be a positive in your application and likely differentiate you from other candidates.
I want to be clear however that how often and how quickly an academic publishes can vary quite considerably depending on the particular research field in question. Generally speaking, STEM fields tend to publish more often than non-STEM areas. There’s variability within STEM too, with factors such as the time taken to complete experiments having an impact on the rate of output. Many PhD students do not publish at all while earning their degree (although I personally believe that at least going through the process of acquiring publications should be part of every PhD experience).
Being able to list publications on your CV and application to PhD programs is a good bonus to have as a student but few potential supervisors or universities would see this as an expectation, let alone a requirement of applying. What he or she will expect to see in you however is the ability to develop your skills to become a researcher who can publish. You should understand at least the broad concepts of what peer-review is and how one may approach the process of writing a paper for journal submission.
Beyond having published work, there are several other ways in which you could demonstrate your research acumen potential. These may include an examples of where you have presented the results of undergraduate or masters projects at internal or external conferences or gained direct experience of working within a research lab alongside PhD students.
If you are someone who’s be able to acquire several publications along a single research theme and are considering PhD programs, I’d recommend you also consider the option of a PhD by Publication, as well as the traditional degree route. Some universities offer this PhD by Publication option as a way of earning a PhD degree by combining your previous papers into a document that demonstrates how these have made a contribution to knowledge within a single research field. The potential drawbacks however compared to traditional PhD programs is that you’re likely to miss out on some of the PhD student experiences that come along with a traditional program.
To conclude, universities will not expect a potential PhD student to have published when they come to fill in the application to their program. You as the potential student should however make sure you emphasise in your application all the different times or ways in which you demonstrated your ability to think like a researcher. This may even include a letter of recommendation from your undergraduate or master’s project supervisor which may attest to your qualities as a suitable applicant.