CPT vs OPT: What Every International Student Needs to Know About F-1 Work Authorization

If you're an F-1 student trying to figure out how to actually work in the U.S., you've probably run into two acronyms over and over: CPT and OPT. They're both types of work authorization for international students, but they work differently, kick in at different times, and have rules that directly affect each other. Getting CPT vs OPT wrong isn't a small mistake. It can cost you your post-graduation work authorization entirely.

This guide covers what each one is, how they compare side by side, how to apply for both, and the one rule that trips up more students than anything else.

TL;DR

• CPT (Curricular Practical Training) and OPT (Optional Practical Training) are the two main ways F-1 students can work in the U.S., but they have different timing, eligibility rules, and application processes.

• CPT is for training during your program (must be tied to your major and approved by your DSO), while OPT is primarily used after graduation for up to 12 months of work authorization (36 months for STEM).

• The critical rule: 12+ months of full-time CPT makes you ineligible for OPT. Part-time CPT does not count toward this limit.

• Externships through Extern can qualify as CPT depending on your school's policies, and Extern provides documentation to support your CPT application.

• The smart play for most F-1 students is to use part-time CPT during school, preserve full OPT eligibility, and build toward H-1B sponsorship.

Looking for professional experience that qualifies for CPT? Explore Externships at Extern →

So What Are CPT and OPT, Exactly?

Curricular Practical Training (CPT) and Optional Practical Training (OPT) are the two types of practical training available to F-1 international students under U.S. immigration law. CPT lets you work off-campus while you're still enrolled, as long as the work connects directly to your academic program. OPT gives you work authorization related to your field of study, and most students use it after graduation.

Both come from the same regulation (8 CFR 214.2(f)(10)), but the way you get them, when you can use them, and what they cost are all different.

CPT in Plain English

CPT is work authorization that your school gives you. The catch is it has to be an integral part of your curriculum, meaning your academic program requires the training or gives you credit for it. Think of it as your school signing off: "Yes, this work counts toward your education."

What does that actually look like?

Your Designated School Official (DSO) at your school's international student office reviews your request, confirms the training ties to your major, and endorses your I-20 (the document that proves your F-1 status). You need all of that done before you start working. Not after. Before.

CPT can be part-time (20 hours per week or less) or full-time (more than 20 hours per week). It's authorized for a specific employer, specific dates, and a specific role. You can't freelance with it or bounce between companies.

Most schools also require you to register for an internship or practicum course during the CPT semester, which may come with tuition or course fees.

OPT in Plain English

OPT is work authorization that comes from USCIS (U.S. Citizenship and Immigration Services), not your school. It lets you work in a position related to your major for up to 12 months. The version most people care about is post-completion OPT, which starts after you finish your degree.

There's also pre-completion OPT (during your program), but honestly most students use CPT during school instead. CPT doesn't require a USCIS filing or a fee, so it's simpler.

If you're in a STEM field, you can extend OPT by an additional 24 months through the STEM OPT extension, giving you up to 36 months total. That extra time matters a lot, because it gives you more shots at the H-1B lottery.

To get OPT, you file Form I-765 with USCIS and pay a $410 application fee. Processing takes 90 to 180 days, and you receive an Employment Authorization Document (EAD) card when approved. You cannot start working until you have that card in hand.

What's the Actual Difference Between CPT and OPT?

The biggest difference between CPT and OPT comes down to timing and process. CPT is training during your program that your school authorizes. OPT is work authorization from USCIS that's primarily used after graduation. But the details matter, because getting one wrong can literally cost you the other.

CPT vs OPT Side by Side

The 12-Month Rule That Catches Everyone Off Guard

If you accumulate 12 months or more of full-time CPT (more than 20 hours per week), you become permanently ineligible for OPT at that education level.

Read that again, because it's the single most important thing in this article.

That's not 12 months total CPT. It's 12 months of full-time CPT specifically.

Part-time CPT (20 hours per week or less) does not count toward this limit at all. You could do part-time CPT every single semester and still qualify for the full 12 months of OPT after graduation.

This is why the part-time model matters so much. If you're doing an Externship through Extern on CPT, the part-time structure means you're building real professional experience without touching your OPT eligibility. Not even a little.

The move for most F-1 students: use part-time CPT during school to gain experience, then save your full OPT for after graduation when you need full-time work authorization.

Who's Eligible for CPT? Who's Eligible for OPT?

The eligibility rules are different for each, and your DSO will check every single one before approving anything. No exceptions.

CPT eligibility:

• You must have been enrolled full-time for at least one full academic year (two semesters or three quarters). Exception: graduate students whose programs require immediate practical training.

• You must be currently enrolled full-time.

• The training must be directly related to your major.

• Your academic program must require or offer credit for the training (internship/practicum course).

• You need an employer offer letter before applying.

OPT eligibility:

• You must be enrolled at a SEVP-certified school.

• You must be in valid F-1 status.

• You must not have already used 12 months of OPT at your current education level.

• You must not have accumulated 12+ months of full-time CPT.

• For STEM OPT extension: your degree must be on the STEM Designated Degree Program List, and your employer must be enrolled in E-Verify.

How Do You Actually Apply for CPT vs OPT?

The application processes are completely different experiences. CPT is handled at your school and can be wrapped up in days. OPT goes through the federal government and takes months. Plan accordingly.

Applying for CPT

First, confirm you're eligible: one full academic year completed, enrolled full-time, and the position relates to your major. Your school's international student office can verify this quickly.

Then you need an employer offer letter. It needs company letterhead, your job title and description, supervisor name and contact info, employment dates, and whether it's part-time or full-time. Externship offer letters from Extern include all of this.

Next, register for the required course. Most schools want you enrolled in an internship or practicum course during the CPT semester. Check your department's requirements and any fees.

Finally, bring everything to your DSO. They update your record in SEVIS and issue an endorsed I-20 with CPT authorization. This is the step that actually turns on your work authorization. Do not start working until you have this endorsed I-20 in your hands.

Applying for OPT

Start by requesting an OPT recommendation from your DSO. They'll update your SEVIS record and give you the documents you need for your USCIS filing.

Then file Form I-765 with USCIS along with the $410 fee, passport photos, copies of your I-20 and I-94, and any other required documents. You can file up to 90 days before your program end date and up to 60 days after. Don't miss this window.

After that, you wait. Processing typically takes 90 to 180 days. You cannot begin working until USCIS approves your application and you receive your EAD card. This waiting period is frustrating, and there's no way around it.

Once you have the EAD, you can start working for any employer in a position related to your field of study. Report your employer information to your DSO within 10 days of starting.

For the STEM OPT extension, file a new I-765 before your initial OPT expires. Your employer must be enrolled in E-Verify, and you'll need a formal training plan (Form I-983).

Don't wait until senior year to build professional experience. Browse Externship programs that support CPT →

Can Externships Qualify for CPT?

Yes, Externships through Extern can qualify for CPT authorization, depending on your school's policies. CPT requires the training to be an integral part of your academic program, so the deciding factor is whether your school's international student office accepts the Externship as qualifying practical training. Most do, but you need to check.

What Extern Provides for Your CPT Application

Extern gives you the documentation that schools typically require for CPT approval. You get an offer letter on company letterhead with your name, role description, dates, hours per week, and supervisor contact information. You also get program documentation describing the Externship structure, learning objectives, and deliverables, plus supervisor information for the extern manager who oversees your project.

Because most Externships are part-time and project-based, they fit naturally into part-time CPT. You're gaining professional experience, building real resume lines, and keeping your OPT eligibility completely intact. That's the combination you want.

Extern has supported international students through the CPT process before, and the documentation is designed to meet common requirements. That said, every school has its own policies, so always confirm with your DSO before applying.

Can You Earn Academic Credit Through an Externship?

Many schools allow students to earn internship or practicum credit for Externship experiences. This can satisfy the course registration requirement that most CPT applications need.

How it works varies. Some departments have a standing internship course you can enroll in. Others require you to arrange credit through an academic advisor. Extern can provide project descriptions and learning outcomes documentation to support the credit approval process.

Check with your academic department and international student office to confirm your school's specific policies.

What Are the Rules You Need to Follow?

Both CPT and OPT come with compliance rules that are serious. Breaking them can result in losing your F-1 status, which means losing your legal ability to stay in the U.S. These aren't guidelines. They're requirements.

CPT Compliance

You cannot begin working until your DSO has endorsed your I-20 with CPT authorization. Starting even one day early is a violation of your F-1 status. This one gets students in trouble more than you'd think.

Your authorization is for one specific employer. Working for a different company, or even changing your role significantly, requires new authorization from your DSO.

You must stay enrolled full-time while on CPT (with limited exceptions during summer). Dropping below full-time can terminate your CPT and put your entire F-1 status at risk.

And if you're on full-time CPT, track your hours carefully. Every month counts toward the 12-month limit that affects OPT. Keep records.

OPT Compliance

On post-completion OPT, you cannot be unemployed for more than 90 aggregate days. For STEM OPT, the limit extends to 150 days. Go past that, and you risk falling out of status. This clock starts ticking the day your OPT begins, so having a job lined up before graduation is a real advantage.

You must report any employer changes, address changes, or interruptions in employment to your DSO within 10 days. Not doing this is one of the most common accidental violations.

Your employment has to be directly related to your field of study. Working in an unrelated field is a violation, even if you have a valid EAD.

For STEM OPT specifically, your employer must be enrolled in E-Verify. You need a formal training plan (Form I-983) signed by both you and your employer. Self-employment is allowed but comes with additional reporting requirements.

How Do CPT and OPT Fit Into Your Long-Term Career?

CPT and OPT aren't just work permits. They're the first two steps in a career pathway that can lead to H-1B sponsorship and long-term employment in the U.S. The way you use them now shapes what's available to you later.

Building Your Resume During CPT

CPT is your first real chance to get U.S. professional experience on your resume. That matters more than a lot of students realize. Employers evaluating you for OPT roles (and eventually H-1B petitions) want to see that you've already worked in a U.S. professional context.

Externships through Extern give you real project work with real companies. You come out with specific deliverables, a professional reference from your extern manager, and concrete resume lines that go well beyond "coursework" and "class projects."

For students in competitive fields like tech or finance, having CPT experience on your resume tells employers you already understand U.S. work culture. That's a real edge when you're competing for full-time roles after graduation.

From CPT to OPT to H-1B: Connecting the Dots

Each stage sets up the next. Here's how they connect:

The progression matters because each step builds your case for the next. CPT experience on your resume makes you more competitive for OPT roles. OPT performance gives your employer a reason to sponsor your H-1B. And the H-1B lottery is competitive enough that employers need to be convinced you're worth the investment. That conviction usually starts with the work you did during CPT.

Frequently Asked Questions

Does part-time CPT affect my OPT eligibility?

No. Part-time CPT (20 hours per week or less) does not count toward the 12-month threshold that makes you ineligible for OPT. You can do multiple semesters of part-time CPT and still apply for full OPT after graduation. Only full-time CPT (more than 20 hours per week) accumulates toward the 12-month limit.

Can I do CPT and OPT at the same time?

No. CPT is only available while you are enrolled in your academic program, and post-completion OPT begins after your program ends. Pre-completion OPT is possible during enrollment, but most schools advise using CPT instead since it does not require USCIS filing or fees. You cannot hold both authorizations simultaneously.

How long does it take to get OPT approved?

USCIS processing for OPT typically takes 90 to 180 days from the date you file your I-765. You should apply as early as 90 days before your program end date. Plan ahead because you cannot work until you receive your EAD card, even if your graduation date has passed.

Can I do CPT for a remote position?

Yes. CPT authorization covers both in-person and remote positions, as long as the training is tied to your academic program and your DSO approves it. Remote Externships through Extern have been used by international students for CPT authorization, though you should confirm with your school's international office first.

What happens if I use 12 months of full-time CPT?

You permanently lose eligibility for OPT at that education level. This means no post-graduation work authorization through OPT, and no STEM OPT extension. This is why most advisors recommend using part-time CPT whenever possible, or carefully tracking your full-time CPT months to stay under 12.

Your classmates are already building professional experience. Start yours today. Explore Externships →