CASPA Application Timeline: When to Take Each Prerequisite Course- because CASPA is rolling and verification takes weeks, the real deadline for finishing your prerequisites is far earlier than you think. Here’s how to work backward from submission and sequence each course.
THE QUICK ANSWER
CASPA opens in late April and runs to the following April, but the deadline that matters is the rolling-admissions clock: most programs review applications as they arrive, so the strategic goal is to submit early — ideally by early June. Because verification takes about four to six weeks at peak, and your prerequisites should be done (or nearly done) when you submit, you need to work backward from a June submission to figure out when each course must be finished.
In practice, that means finishing most prerequisites in the year before you apply, sequencing foundational courses before advanced ones, and using self-paced courses to hit your dates. Always confirm exact deadlines on CASPA and each program’s site.
Most pre-PA applicants understand they need prerequisites. Far fewer understand when each one has to be done — and that gap is one of the most common reasons capable applicants lose a cycle. They assume that because a program’s deadline is in the fall, they have until fall to finish coursework. By then, rolling admissions has often already worked against them.
The truth is that the PA application calendar runs backward from a much earlier date than the published deadline. Once you understand how the CASPA timeline actually works — the rolling review, the verification lag, and the early-submission advantage — you can reverse-engineer exactly when each prerequisite needs to be complete. This guide walks through that timeline and turns it into a concrete course-sequencing plan, so your prerequisites are finished when they need to be, not a semester too late.
CASPA — the Centralized Application Service for Physician Assistants, run by the Physician Assistant Education Association (PAEA) — is used by roughly 180+ programs, about 90% of accredited PA programs. Its cycle is unusually long: it opens in late April and runs until early April of the following year. For the current cycle, CASPA opened April 30 and closes the following April 1. That long window fools a lot of applicants into thinking they have plenty of time. Three features of how it works explain why they don’t:
Put together, these create one clear conclusion: the goal is to submit early. A widely-cited target is submitting by around early June, which lets verification finish before the worst of the summer backlog and gets your application in front of programs while seats are plentiful. Everything about your prerequisite timing flows from that early-submission goal.
Here’s the key insight that reorganizes your whole plan: your prerequisites need to be done much earlier than the application deadline. Working backward from an early-June submission in your application year:
| When | What Should Be Happening |
| 12–18 months before applying | Complete the bulk of your prerequisites — especially long sequences (A&P I & II, Gen Chem I & II). This is where most of your coursework should happen. |
| Spring before applying (by April) | Finish any remaining prerequisites, or be in your final term. Grades for completed courses should be on official transcripts you can send to CASPA. |
| Late April (cycle opens) | Request official transcripts immediately; enter coursework. Transcript and coursework entry is a common verification bottleneck — do it first. |
| By early June (“golden goal”) | Submit your verified-ready application. Prerequisites complete or clearly in progress with a finish date programs accept. |
| Summer / early fall | Any approved “in progress” prerequisites are completed by each program’s required date. Interviews begin. |
Illustrative; exact dates vary by cycle and program. Some programs allow a limited number of prerequisites to be “in progress” at application with a completion deadline; others require all prerequisites done before applying. Always verify each program’s rules.
Notice the implication: if you want to submit in early June, the spring immediately before is your last comfortable window to finish coursework — which means the heavy lifting happens in the 12–18 months prior. For most applicants with several prerequisites left, that’s a year-plus of planned, sequenced coursework. The earlier you map it, the less likely a single late course derails your whole cycle.
Can you apply with prerequisites still in progress? Sometimes — but it’s risky to count on. Policies vary widely: some programs let you apply with a limited number of prerequisites in progress as long as they’re finished by a stated date; others require everything complete before you apply; and competitive programs often prefer applicants who are already done, because completed grades are proven, not promised.
There’s also a GPA dimension. An in-progress course contributes no grade yet, so it can’t help your science GPA at the moment programs first review you under rolling admissions. If your science GPA needs strengthening, finishing those courses before you submit — so the strong grades are visible — is far more powerful than carrying them as in-progress. The safe planning assumption: aim to have prerequisites done before submission, and treat “in progress” as a narrow fallback you’ve confirmed each program allows.
With the timeline clear, here’s how to order the actual courses. Good sequencing respects two things: which courses build on others, and which courses most programs require (so you finish the essentials first).
Some prerequisites are gateways to others and should come first:
If you have a long list, complete the courses almost every program requires first — anatomy and physiology, microbiology, general chemistry, and statistics — so your core is done while you finalize your school list. Program-specific or less common requirements (organic chemistry, biochemistry, a second biology) can follow once you know exactly which programs you’re targeting. See the full breakdown in our PA prerequisite course guide.
Many programs reject prerequisites older than 5–10 years. Don’t complete a time-sensitive science course so early that it risks aging out by the time you apply — and if you have old credits, time their retakes so they’re recent at application. Recency is part of sequencing, not just a separate rule.
This is where the timeline and your course choices meet. Fixed-schedule courses lock you into a school’s calendar, which may not align with your June target. Self-paced courses let you start when you need to and finish on your timeline — so you can complete a sequence in the specific window your plan requires, around work or other commitments. For applicants racing a rolling-admissions clock, that scheduling control is exactly what keeps a plan on track.
The single biggest timeline mistake is treating prerequisites one at a time — finishing one course, then deciding what’s next, then enrolling, then waiting. That stop-start approach burns months you may not have before your target submission date.
Instead, map your entire prerequisite sequence up front: list every course you need, order them by dependency and program-frequency, assign each to a window working backward from your early-June submission goal, and enroll in the right courses at the right times so sequences flow without gaps. Planning the full sequence — and lining up the courses that can run in parallel — is how you compress a long prerequisite list into the time you actually have, instead of discovering in your application spring that you’re a course or two short.
Because PrereqCourses.com courses are self-paced and accredited (delivered through Upper Iowa University, HLC-accredited), you can enroll in the courses your timeline calls for and complete them on the schedule your plan requires — including running compatible courses at once to stay on pace. Browse the full catalog to map your sequence, and use our guide to completing prerequisites while working to build a realistic week-to-week routine.
When should I submit my CASPA application?
As early as you reasonably can — a widely-cited target is early June of your application year. Because most programs use rolling admissions and verification takes about four to six weeks at peak, submitting early gets your application in front of programs while seats and interview slots are plentiful. Waiting until a fall deadline often means competing for a much smaller pool.
When do my prerequisites need to be finished for PA school?
Earlier than you might think. To submit by early June, you generally want prerequisites complete (or in your final term) by the spring immediately before you apply, which means most coursework happens in the 12–18 months prior. Some programs allow a limited number of prerequisites to be “in progress” with a completion deadline, but many prefer or require them done before applying — verify each program’s rule.
Can I apply to PA school with prerequisites in progress?
Sometimes, but don’t rely on it. Policies vary: some programs permit a limited number of in-progress prerequisites with a stated completion date, others require all prerequisites complete before applying, and competitive programs often prefer finished applicants. In-progress courses also contribute no grade yet, so they can’t help your science GPA at the moment programs first review you. Aim to finish before submitting when possible.
How long does CASPA verification take?
Approximately four to six weeks during the busy May–June submission period, though it can be faster outside the peak. Your application isn’t sent to programs until it’s verified, so a June submission may not reach programs until July. Requesting transcripts early and entering coursework accurately helps avoid verification delays.
What order should I take PA prerequisites in?
Take foundational courses before advanced ones — general chemistry before organic chemistry or biochemistry, and the first half of a sequence before the second (A&P I before A&P II). Front-load the near-universal requirements (anatomy and physiology, microbiology, general chemistry, statistics) so your core is done first, and slot in standalone courses like statistics and psychology flexibly. Mind recency windows so courses don’t age out.
How far in advance should I start my prerequisites?
If you have several prerequisites to complete, plan for roughly 12–18 months of sequenced coursework before your application cycle, finishing the bulk in that window so everything is done by the spring before you submit. Mapping the full sequence up front — and running compatible courses in parallel — lets you fit a long list into the time available without losing a cycle.
The CASPA calendar rewards applicants who plan backward. Because admissions are rolling and verification takes weeks, the real target is an early-June submission — which means your prerequisites need to be finished by the spring before you apply, and the bulk of your coursework belongs in the 12–18 months prior. Sequence foundational courses before advanced ones, front-load the near-universal requirements, mind recency windows, and map the whole sequence at once rather than one course at a time. PrereqCourses.com offers accredited, self-paced prerequisite courses you can complete on the schedule your timeline demands — so you reach your submission date with your prerequisites done, not pending.
Map Your Prerequisite Sequence — and Hit Your Submission Date
PrereqCourses.com delivers accredited, self-paced prerequisite courses through Upper Iowa University (HLC-accredited) — start when your timeline calls for it, run compatible courses in parallel, and finish on schedule. Work backward from your CASPA submission goal, map your full sequence, and complete every prerequisite before it’s due.
This guide is for general planning. CASPA cycle dates, verification times, and each program’s deadlines, in-progress rules, and prerequisite recency requirements vary by cycle and program. Always verify current dates and requirements directly with CASPA and with each PA program before building your timeline.
