The United States has roughly 2,000 to 2,500 aquariums, though the exact number shifts depending on how you count them

There is no single official registry of aquariums in the United States, so the count varies by source and by what counts as an aquarium. Public aquariums — the large facilities you visit with paid admission — number somewhere between 50 and 100. The rest are smaller operations: roadside attractions, educational centers run by nonprofits, research facilities, and aquariums inside zoos or museums. Some sources count only facilities open to the public; others include research-only tanks. This is why you will see different numbers depending where you look.

The largest and most visited aquariums are concentrated in coastal cities and major metropolitan areas. The Georgia Aquarium in Atlanta, the Monterey Bay Aquarium in California, and the National Aquarium in Baltimore are among the most well-known. Smaller public aquariums exist in nearly every state, often run by local governments, universities, or conservation nonprofits. Many are regional attractions rather than destinations people travel across the country to see.

Key Takeaways

  • Public aquariums open to paying visitors number between 50 and 100 in the United States, with the rest being smaller facilities, research centers, or exhibits within other institutions.
  • The total count of all aquariums — including small educational tanks, research facilities, and zoo-based exhibits — reaches into the thousands, but no federal agency maintains a definitive list.
  • Coastal states and major cities have the highest concentration of public aquariums because of population density and access to saltwater species.
  • Many aquariums are run by nonprofits focused on conservation and education rather than by for-profit entertainment companies.

Why the count is uncertain

The United States does not have a central database of aquariums. The Association of Zoos and Aquariums (AZA) accredits facilities that meet specific standards for animal care, education, and conservation, but accreditation is voluntary. An aquarium does not have to join AZA to operate legally. This means smaller facilities, roadside attractions, and research-only operations may not appear in any national count.

The definition of "aquarium" also matters. A large public facility with multiple tanks and thousands of visitors per year looks nothing like a small educational center in a school or library. Some people count only public aquariums; others include every tank-based exhibit. Research institutions that study fish but do not open to the public are sometimes included and sometimes not. This variation is why different sources report different totals.

Where public aquariums are located

The largest concentration of major public aquariums is on the coasts. California, Florida, and the Northeast have multiple large facilities because of coastal access and population. Inland states have fewer large aquariums, though most states have at least one public facility. Texas, Georgia, and Ohio each have several significant aquariums despite being inland or partially inland.

City size matters more than geography. Aquariums are expensive to build and operate, so they tend to exist in metropolitan areas where enough people visit to cover costs. A city of 500,000 is more likely to support a public aquarium than a city of 50,000. This is why you will find multiple aquariums in the New York area, Los Angeles, and San Francisco, but only one or two in most states.

Types of aquariums and what they do

Public aquariums vary widely in size and focus. Some specialize in local species — a freshwater aquarium in the Midwest might focus on native fish and turtles, while a coastal aquarium displays saltwater species. Others are general-interest facilities with a mix of freshwater and saltwater exhibits. A few, like the Georgia Aquarium, are massive operations with whale sharks, beluga whales, and thousands of other animals.

Beyond public aquariums, the count includes research facilities at universities and government agencies, educational exhibits in zoos and museums, and smaller community centers. Many of these are not open to the general public or charge no admission. They exist to study fish behavior, breed endangered species, or teach students about aquatic ecosystems. These facilities are harder to count because they are not listed in tourism directories or travel guides.

How many people visit aquariums each year

The major public aquariums draw millions of visitors annually. The Georgia Aquarium alone receives over 10 million visits per year, making it one of the most visited attractions in the United States. Smaller public aquariums typically draw between 100,000 and 1 million visitors per year, depending on location and size. Combined, public aquariums are a significant part of the tourism and education landscape.

Visitor numbers have shifted over time. Some aquariums saw drops during the COVID-19 pandemic and have been rebuilding attendance. Others have remained stable or grown. Newer facilities and those with unique attractions — like touch pools or interactive exhibits — tend to draw more visitors than older, more traditional setups.

The role of nonprofit and conservation organizations

Many aquariums in the United States are run by nonprofits rather than for-profit companies. Organizations like the Monterey Bay Aquarium, the Shedd Aquarium in Chicago, and the New England Aquarium in Boston are all nonprofit institutions. These facilities often reinvest revenue into conservation work, research, and education rather than paying shareholders. They may also receive grants and donations that help fund operations.

Nonprofit aquariums often focus on specific conservation goals — protecting endangered species, restoring habitats, or researching ocean health. This mission-driven approach shapes what animals they keep, what research they conduct, and what they teach visitors. For-profit aquariums, by contrast, prioritize attendance and revenue, though many also support conservation in some form.

Accreditation and standards

The Association of Zoos and Aquariums (AZA) sets standards for animal care, staff training, and conservation work. Facilities that meet these standards can become accredited members. AZA accreditation is a mark of quality and is often listed on an aquarium's website. However, not all aquariums pursue accreditation, and some smaller facilities operate without it.

State and local regulations also govern aquariums. Fish and wildlife agencies set rules about which species can be kept, how tanks must be maintained, and what permits are required. These rules vary by state and sometimes by county. An aquarium in one state might be able to keep species that are illegal in another. This patchwork of regulations is one reason why aquarium operations and standards differ across the country.

Frequently Asked Questions

What is the largest aquarium in the United States?

The Georgia Aquarium in Atlanta is the largest by most measures, with over 10 million gallons of water and more species than any other U.S. aquarium. It is also the most visited, drawing over 10 million guests per year. The Monterey Bay Aquarium in California is often considered the most prestigious and is known for its research and conservation work.

Can I find a list of all aquariums near me?

The Association of Zoos and Aquariums website lists accredited facilities by state, which is a good starting point. Travel and tourism websites also list public aquariums by location. For smaller or research-only facilities, a local search or call to your city's tourism office may be needed, since not all facilities are widely advertised.

Are there more aquariums now than there were 20 years ago?

The number of large public aquariums has remained relatively stable, though some older facilities have closed and new ones have opened. Smaller educational aquariums and exhibits have likely increased as schools and nonprofits add them. Overall growth has been modest, as building and operating an aquarium requires significant capital and ongoing funding.

Do all aquariums keep the same types of fish?

No. Aquariums vary widely in what they keep. Some focus on local freshwater species, others on tropical fish, and still others on deep-sea creatures or marine mammals. The animals an aquarium keeps depend on its mission, its location, available funding, and what species it is licensed to keep under state and federal law.