Hawaii is the one place in America where your sunscreen is a legal question before it is a shopping question. The state bans the sale of sunscreens containing oxybenzone and octinoxate, Maui County bans the use of anything that is not mineral, and the Big Island restricts sales the same way — and none of that appears anywhere on the front of the bottle, where the words “reef safe” are printed in large friendly letters and mean, legally, nothing at all. There is no agency that certifies a sunscreen as reef safe. Any brand can use the words.
So this guide ignores the front of the bottle. It teaches the only check that works — the active-ingredients panel on the back — then walks the law island by island, explains the nano argument honestly, and finishes with the part most sunscreen guides never reach: how to actually use mineral sunscreen across a snorkeling day, when the best sun protection in the water is not a cream at all but the rash guard over your back. Everything on this page is written for snorkelers, because snorkelers spend longer face-down in reef water than anyone else at the beach — and because the spots this site covers, from Hanauma Bay to the ‘Ahihi-Kina’u reserve coast, are exactly the places where the rule matters most.
Quick answer
- The only check that works: turn the bottle over. The active ingredients must be zinc oxide, titanium dioxide, or both — and nothing else. If any chemical filter (oxybenzone, octinoxate, avobenzone, octocrylene, homosalate, octisalate) appears in the active panel, it is not mineral, whatever the front claims.
- The law in one line: Hawaii state law (Act 104) bans the sale of oxybenzone/octinoxate sunscreens; Maui County bans the sale and use of all non-mineral sunscreens; Hawai’i County (the Big Island) bans the sale of non-mineral sunscreens; Oahu and Kauai follow the state baseline.
- The snorkeler’s rule: wear a long-sleeved rash guard so most of your skin needs no sunscreen at all, use mineral lotion or a face stick on what is left, apply it before you reach the beach, and reapply on the label’s clock — water-resistant means 40 or 80 minutes in the water, never “waterproof.”
- SPF: broad-spectrum SPF 30 or higher, per dermatology guidance. Mineral SPF 30 applied properly beats chemical SPF 70 applied thin.
The 30-second label check
Stand in the shop, pick up the bottle, and do exactly this:
- Find “Active ingredients.” It is in the Drug Facts panel on the back, not in the marketing copy.
- Read the list, all of it. Pass: the list contains only zinc oxide and/or titanium dioxide. Fail: it contains anything else — most often avobenzone, octocrylene, homosalate or octisalate in products that are legal to sell in Hawaii under state law but are not mineral and are not allowed for use in Maui County.
- Ignore the front completely. “Reef safe,” “reef friendly,” “Hawaii compliant,” “ocean friendly” and a coral logo are unregulated claims. Hawaii-compliant is the slipperiest of them: it can mean nothing more than “no oxybenzone or octinoxate,” which still leaves a fully chemical sunscreen that Maui County prohibits using.
- Check water resistance while you are there. For snorkeling you want “water resistant (80 minutes)” on the label. Forty minutes is the other standard rating. There is no such thing as a waterproof sunscreen — the term is not permitted on US labels because every formula washes off eventually.
- One purist detail, honestly labelled as debated: some otherwise-mineral products use butyloctyl salicylate as an inactive ingredient to boost SPF; strict reef advocates flag it because it is a chemical UV-absorber cousin, regulators do not ban it, and it does not affect your legal position anywhere in Hawaii. Know it exists; do not let it paralyse the purchase.
That is the whole skill. It takes thirty seconds, it works in any shop in any country, and it will never be out of date the way a brand list goes out of date when formulas change — which they do, silently, which is why this guide checks panels rather than crowning bottles.
Hawaii’s sunscreen law, island by island
| Where | Rule | What it bans | Sale or use? |
|---|---|---|---|
| All of Hawaii (state law, Act 104, in force since 1 Jan 2021) | No sunscreen containing oxybenzone or octinoxate may be sold or distributed in the state without a prescription | Two named chemical filters | Sale/distribution only — the state law does not fine you for applying a bottle you brought from home |
| Maui County — Maui, Molokai, Lanai (Ordinance 5306, in force since 1 Oct 2022) | Only mineral sunscreens (zinc oxide and/or titanium dioxide as the active ingredients) may be sold, distributed or used without a prescription | Every non-mineral sunscreen | Sale and use — the strictest rule in the state, and the one snorkelers actually meet |
| Hawai’i County — the Big Island (County Code 14-30 to 14-31, in force since 1 Dec 2022) | Only mineral sunscreens may be sold or distributed without a prescription | Every non-mineral sunscreen | Sale/distribution (not a personal-use ban like Maui’s) |
| Oahu and Kauai | No stricter county mineral rule at the time of writing — the state Act 104 baseline applies | Oxybenzone/octinoxate products cannot be sold | Sale only, via the state law |
The practical translation for a trip: if you island-hop — and most snorkeling trips do — a chemical sunscreen that is merely unsellable in Honolulu becomes actually prohibited to use the day you land on Maui. Packing one mineral sunscreen for the whole trip is not eco-virtue; it is simply the only packing decision that is legal and welcome everywhere in the state. It is also what protected places expect of you regardless of county lines: Hanauma Bay’s visitor programme pushes reef-safe choices hard, the ‘Ahihi-Kina’u reserve asks for mineral protection in the water at spots like La Perouse Bay, and many snorkel tour boats hand out mineral sunscreen on board or ask guests not to apply chemical formulas before entering the water — ask your operator rather than assuming, but never be surprised by it.
A note on honesty about enforcement: nobody is stationed at Kapalua checking tubes. The state law works because Hawaii shops simply do not stock the banned products; the Maui use ban works mostly as a norm that locals, lifeguards, rangers and operators will point out. Visitors who treat it as real anyway are the reason it works — and the reef over which you will spend your morning is the direct beneficiary.
What “reef safe” actually means — and what it doesn’t
The science that started all of this is narrower than the marketing built on it. Laboratory studies linked oxybenzone in particular to coral bleaching stress, larval deformity and endocrine effects in marine organisms, and Hawaii legislated against the two best-evidenced filters first. That is a real, defensible basis for Act 104. What the science does not give you is a certified list of “safe” products: no regulator tests and approves sunscreens for reef safety, studies use concentrations and conditions that do not map neatly onto a snorkeler over a reef flat, and researchers continue to debate how large sunscreen’s share is next to warming water, runoff and sediment — the reef’s much bigger problems.
The honest position, and the one this site takes across its coral reef snorkeling guide, is a layered one. Mineral filters sit on the skin and scatter UV rather than absorbing into it, zinc and titanium are the filters every Hawaii rule converges on, and choosing them costs you almost nothing — modern mineral formulas are genuinely good. So choose mineral, skip the halo, and put your remaining effort into the things with the largest certain effect: not standing on coral, not feeding fish, keeping your fins off the bottom, and covering your skin with fabric so less of anything enters the water. That ordering — law, then label, then behaviour — is worth more to the reef than any single bottle.
Nano vs non-nano: the honest version
Mineral sunscreens work with particles of zinc oxide or titanium dioxide. “Nano” versions mill those particles below 100 nanometres so the cream rubs in without the classic white cast; “non-nano” versions leave the particles larger, apply whiter, and are marketed as less likely to be ingested by coral and filter feeders. Here is what is actually established: no law anywhere in Hawaii — or, as far as current rules go, anywhere else — requires non-nano sunscreen; every Hawaii rule is satisfied by any sunscreen whose active ingredients are only zinc oxide and/or titanium dioxide. The evidence that nano mineral particles harm reef life under real ocean conditions is inconclusive; the concern is a reasonable precaution, not a settled finding.
So the choice is yours and it is a small one. If a non-nano formula’s white cast does not bother you, it is the precautionary pick and several snorkel-focused brands formulate that way. If a nano mineral formula is the one you will actually apply generously and reapply — the behaviour that protects both your skin and, indirectly, the reef visit itself — it is fully legal and a defensible choice. What does not work is using the nano debate as a reason to reach back for a chemical sunscreen, which fails the law and the label check at once.
The new filter in 2026: bemotrizinol (BEMT)
In June 2026 the US Food and Drug Administration added bemotrizinol — BEMT for short — to its permitted over-the-counter sunscreen active ingredients. It is the first new sunscreen active approved in the United States in 25 years, and it protects against both UVA and UVB. It has been used in sunscreens abroad for years, so the approval is new to the American market, not new to the world.
BEMT is a chemical UV filter, not a mineral one. That single fact decides where it stands in Hawaii. The statewide law, Act 104, bans the sale of sunscreens containing oxybenzone or octinoxate. BEMT is neither, so a BEMT sunscreen clears the state rule and can be sold — and used — on Oahu and Kauai, where the state baseline is the only rule in force.
It does not clear the county rules. Maui County’s mineral-only ordinance bans the sale, distribution and use of any non-mineral sunscreen without a prescription, and BEMT is non-mineral, so a BEMT sunscreen cannot legally be used on Maui, Molokai or Lanai. On the Big Island, the county rule restricts the sale and distribution of non-mineral sunscreen, so a BEMT product falls inside that sales restriction even though personal use is not banned there the way it is on Maui. A formula that blends zinc oxide with BEMT is still non-mineral under the county definitions — the zinc does not rescue it.
So the packing rule on this page does not change: if your trip touches Maui, the only sunscreen that is legal and welcome everywhere in the state is still one whose active ingredients are only zinc oxide and/or titanium dioxide. A BEMT sunscreen is a fine product for a mainland beach day; it is the wrong bottle for a Hawaii trip that includes Maui.
What to buy: formats, not hype
Brands reformulate and bottles change, so buy the format that fits the job and verify it with the label check above. Widely stocked examples appear in most Hawaii shops and ABC Stores after you land — buying on-island is itself a compliance shortcut, because everything on a Hawaii shelf already clears Act 104 (though only the mineral ones clear Maui’s stricter rule).
- Body lotion, mineral, SPF 30–50, water resistant (80 minutes): the workhorse for legs, shoulders and backs not covered by a rash guard. Thinksport, Blue Lizard Sensitive Mineral, Badger Sport and All Good are the names you will see most often in Hawaii shops and in competitor roundups; Raw Elements and Stream2Sea are the snorkel-and-dive-shop regulars. Check the panel anyway — several of these brands also sell chemical lines under similar packaging.
- Face stick: the snorkeler’s format. A mineral stick goes on precisely, stays put better through a mask strap, and does not migrate into your eyes the way creams do when a mask leaks — chemical sunscreen in the eyes inside a leaking mask is one of snorkeling’s genuinely miserable experiences, and mineral sticks largely spare you it. Keep the stick off the strip of forehead where your mask skirt seals; sunscreen there can break the seal and cause the leak in the first place.
- Tinted mineral: the answer to white cast. Tinted zinc formulas (several local and national brands make them) blend far better on most skin tones and double as light face coverage for the beach day around the snorkel. Hawaii-made options such as Kokua Sun Care and Maui Vera sit in most island shops if buying local matters to you.
- For kids and sensitive skin: fragrance-free mineral lotions are the standard recommendation — zinc formulas are the ones dermatologists reach for with eczema-prone and post-procedure skin — and a child’s rash guard does even more work than an adult’s, because children reapply badly and burn fast at the waterline.
- Skip the spray as your main protection. Aerosol and pump sprays under-apply (much of the dose drifts onto sand and into the air on a trade-wind beach), make the two-ounce, full-coverage application almost impossible to judge, and are the format reef programmes most often ask visitors not to use before entering the water. If a spray is all you have, spray close, rub it in by hand, and treat it as a top-up over a lotion base — never as the base itself.
How to use it on a snorkeling day
Cover first, cream second. A long-sleeved rash guard or sun shirt is the single best piece of sun protection a snorkeler owns: it cannot wash off, it does not expire mid-session, it covers exactly the map of a snorkeler’s sunburn — back, shoulders, back of the neck — and it sends nothing into the water. Our snorkel gear checklist treats it as core kit for this reason. Cream what the fabric leaves: face, ears, neck, hands, and the backs of legs and knees, which burn floating at the surface while their owner is looking down.
Apply on land, early. Mineral sunscreen works as soon as it is spread — it is a physical shield, not a chemical reaction — but applying about fifteen minutes before you enter the water lets any sunscreen bind to skin instead of shearing straight off into the shallows, which is the standard guidance and the difference between protection on you and sunscreen in the bay. Apply at the hotel or the car, not standing in the water at a protected bay.
Dose like you mean it. The tested dose behind every SPF number is roughly one ounce — a shot-glass full, about two tablespoons — for an adult body, and about a teaspoon for face and neck. Most people apply a third of that and receive a fraction of the labelled SPF. Mineral formulas make under-application visible: if you cannot see a faint sheen going on, you are probably under-doing it; rub until it settles rather than stopping at the first white streak.
Run the reapply clock, not your memory. Water-resistant (80 minutes) means the formula retained its protection through eighty minutes of water immersion in testing — after a long snorkel session you are at or past the rating, and after towelling off you are past it entirely. Reapply when you come out for a break, at two hours from application at the latest, and immediately after towelling. On a two-session day — a morning at Ulua and an afternoon at Turtle Town — that means sunscreen is a between-sessions ritual, not a morning one.
Mind the mask. Beyond the seal trick above: put face sunscreen on early enough to set, keep cream out of your hairline where the strap sits, and if your eyes sting mid-session, surface, lift the mask and rinse your face with seawater rather than rubbing — mineral residue rinses cleaner than chemical, which is one more small mercy of the format.
Where the rule meets your itinerary
- Maui (all snorkeling, including Molokini tours and the ‘Ahihi-Kina’u coast): mineral is the law for use, not a preference — pack it or buy it on arrival.
- Big Island (Kona and Kohala coasts, Honaunau, Kealakekua): shops can only sell mineral; your brought-from-home chemical bottle is not illegal to use, but the mineral habit is the local norm and what operators expect.
- Oahu (Hanauma Bay, Waikiki, North Shore): state baseline, plus site-level reef programmes at Hanauma that teach exactly the label check above before you enter the water.
- Kauai (Poipu, Tunnels, Hanalei): state baseline; the island’s MPAs and community fisheries programmes ask for the same mineral choice as a matter of reef care.
- Tour boats everywhere: many provide mineral sunscreen on board and some prohibit applying chemical formulas on the boat before a swim stop. Our Hawaii snorkeling tours guide flags what is typically included; check your operator’s confirmation.
Frequently asked questions
Is reef-safe sunscreen required in Hawaii?
Effectively, yes for the choice that matters: Maui County legally requires mineral-only sunscreen for use, Hawai’i County restricts sales to mineral-only, and statewide the two most common chemical filters cannot be sold at all. A mineral sunscreen — only zinc oxide and/or titanium dioxide as active ingredients — is compliant and welcome on every island.
What sunscreen ingredients are banned in Hawaii?
Statewide, sunscreens containing oxybenzone or octinoxate cannot be sold or distributed without a prescription (Act 104, since 2021). In Maui County and Hawai’i County the restriction is broader: any non-mineral sunscreen — including formulas built on avobenzone, octocrylene, homosalate or octisalate — falls under the county mineral-only rules (sale and, on Maui, use).
Can I bring my regular sunscreen from home?
You can fly with it, and on Oahu and Kauai no law stops you using it — but you cannot use it on Maui, you will not be able to buy a replacement like it anywhere in Hawaii, and at protected bays and on tour boats you may be asked not to apply it. One mineral bottle for the trip is simpler and legal everywhere.
How can I tell if a sunscreen is really reef safe?
Ignore the front label — “reef safe” is unregulated and uncertified. Read the active-ingredients panel: only zinc oxide and/or titanium dioxide means mineral and compliant with every Hawaii rule. Anything else in that panel means it is not mineral, whatever the coral logo says.
Does mineral sunscreen work as well as chemical sunscreen?
Yes, when applied at the tested dose and reapplied on schedule — broad-spectrum SPF 30 or higher is the standard dermatology recommendation, and mineral filters protect across UVA and UVB. Where mineral formulas underperform in real life is application: they are thicker, easier to under-apply and quicker to show white cast, which is why the dosing and tinted-formula advice above matters. Our beginners’ snorkeling guide covers the first-session routine this fits into, and the snorkeling safety guide covers the wider hazard picture.
Is non-nano sunscreen required in Hawaii?
No. No Hawaii rule requires non-nano particles; any zinc oxide / titanium dioxide-only sunscreen satisfies every law in the state. Non-nano is a personal precaution some snorkelers prefer while the research on nano particles under real reef conditions remains inconclusive.
When should I apply sunscreen before snorkeling?
About fifteen minutes before entering the water, on land. That lets the formula bind to your skin so it protects you instead of washing straight into the shallows, and it gives face sunscreen time to set so it does not break your mask seal or sting your eyes.
What is the best sun protection for snorkeling, if not sunscreen?
A long-sleeved rash guard. It covers the back, shoulders and neck — the exact surfaces that burn while you float face-down — it never washes off, needs no reapplication, works at full strength all session, and puts nothing into the water. Sunscreen then only has to cover face, ears, hands and the backs of your legs.
What sunscreens are allowed in Hawaii?
The sunscreen that is allowed everywhere in Hawaii is a mineral one: zinc oxide and/or titanium dioxide as the only active ingredients. Statewide, sunscreens containing oxybenzone or octinoxate cannot be sold. Maui County goes further and bans the use of any non-mineral sunscreen, and Hawai’i County restricts sales to mineral-only. Oahu and Kauai follow the state baseline. One mineral bottle for the whole trip is the only choice that is legal and welcome on every island — and it is also what the protected bays and tour boats expect.
Is bemotrizinol (BEMT) sunscreen allowed in Hawaii?
It depends on the island. BEMT is a chemical UV filter the FDA approved for over-the-counter use in June 2026. It is not oxybenzone or octinoxate, so it clears the statewide sales ban and can be used on Oahu and Kauai. But it is not mineral, so Maui County’s mineral-only rule bans using it on Maui, Molokai and Lanai, and Hawai’i County’s rule restricts selling it on the Big Island. A zinc-plus-BEMT blend is still non-mineral under the county rules. If Maui is on your itinerary, leave the BEMT bottle at home.
Is Hawaiian Tropic sunscreen reef safe?
Not as a brand — as a bottle. Hawaiian Tropic sells both chemical and mineral lines, and some of its formulations still contain oxybenzone or octinoxate. Its mineral line, such as the Mineral Skin Nourishing Milk, lists only titanium dioxide and zinc oxide as active ingredients, and that passes the check. The “reef friendly” badge on the front is not the test; turn the bottle over and read the active-ingredients panel. Only zinc oxide and/or titanium dioxide, and nothing else, means it is mineral and compliant with every Hawaii rule. The same panel test applies to every brand, including Blue Lizard, whose Sensitive Mineral line is already in the buying guide above.
Is there a certified reef-safe label I can trust?
No government agency defines or certifies “reef safe”, so no label on the front of a bottle carries legal weight. The closest thing to a real certification is the Protect Land + Sea seal from the Haereticus Environmental Laboratory, which chemically tests the finished product for a list of known aquatic pollutants rather than just reading the ingredient list. If you see that seal, it is a genuine plus — but still run the 30-second label check above. A seal is a shortcut, not a substitute, and the active-ingredients panel is the check that never goes out of date.