Costs & Certification

Which Scuba Agency Should You Choose?

PADI, SSI, NAUI, SDI and BSAC all certify you to the same global standard. Here's how they differ, and the one thing that matters more than the logo.

By Mat Mora · Updated 17 June 2026 · ~7 min read

PADI, SSI, NAUI, SDI and BSAC are all reputable agencies whose certifications meet the same global training standard and are recognised at dive centres worldwide. The differences are in style and availability, not safety. PADI is the most widely available, SSI is digital-first and flexible, NAUI is education-focused, BSAC is club-based and strong for cold water, and SDI is built around dive computers. The biggest factor in how good your course is, is your instructor, not the logo.

All agencies
Same global standard
Card recognition
Worldwide, mutual
Most available
PADI
Matters most
Your instructor

New divers spend a lot of energy worrying about which agency to choose. Here is the reassuring truth: the major agencies all teach the same core skills to internationally recognised standards, and your entry-level card lets you dive almost anywhere on Earth regardless of whose logo is on it. The real differences are in learning style, materials, and how common each agency is where you plan to dive.

The major agencies at a glance

AgencyKnown for
PADIThe largest and most available; standardised, modular courses
SSIFree digital materials, flexible pacing, dive-centre led
NAUINonprofit, education-first, popular with academic and military programs
SDIModern, computer-based approach from the technical-diving family (TDI)
BSACUK club-based model, excellent for cold water and expedition diving
CMASFederation of national clubs, common across Europe

Most major agencies align their standards through bodies such as the WRSTC and ISO, which is why an Open Water diver from one agency can continue training with another. If you start with one and switch later, you generally will not lose progress.

So how do you actually choose?

  1. Pick the instructor and centre first: A patient, careful instructor at a well-run centre will teach you more, and keep you safer, than any brand. Read reviews, ask about class sizes, and choose people you feel comfortable with.
  2. Consider what's available where you'll dive: If you plan to dive mostly in one region, training with an agency that is common there makes finding courses and continuing education easier.
  3. Think about learning style: Prefer slick app-based theory you can do on the sofa? PADI and SSI suit you. Like a club community and cooler-water skills? BSAC is excellent.
  4. Don't over-optimise: Any reputable agency will certify you to dive safely. Spend your energy on diving well, not on agency comparison charts.

Where Diving Standard fits in

Whichever agency you train with, Diving Standard follows the same global standard that keeps divers safe. What sets our approach apart is a particular way of looking at the sport:

In other words, get certified with whichever agency suits you, then use Diving Standard to keep learning, dive more mindfully, and look after both yourself and the ocean.

Whichever agency you choose, learn with us

Diving Standard's free lessons follow the same global standard, with a focus on safety, conservation and wellbeing. Start before, during or after your course.

Get the Diving Standard app

Frequently asked questions

Is PADI better than SSI or NAUI?

No agency is meaningfully safer or better than the others. PADI, SSI, NAUI, SDI and BSAC all certify to the same global standard and their cards are recognised worldwide. PADI is simply the most widely available. The quality of your individual instructor matters far more than the agency.

Is my certification recognised everywhere?

Yes. Entry-level certifications from the major agencies are mutually recognised, so a card from one lets you dive and continue training almost anywhere, with any agency.

Can I switch agencies after I start?

Generally yes. Because the major agencies align to shared standards, you can usually continue your training with a different agency without repeating what you've already learned.

About the author

Mat Mora — Advanced Diver (PADI), Deep & Nitrox (SSI), Founder of Diving Standard. He writes these guides to give new and experienced divers clear, trustworthy answers to the questions every diver asks.

Related articles