Find your ZIP code
Search by ZIP, place, or county, or sort a column. Every row is in the HTML, so the table does not depend on JavaScript. The downloadable file is the same 82 rows: radon-zip-tampa-bay.csv.
Florida Department of Health data
Radon levels by ZIP code in Tampa Bay
In the Florida Department of Health database, the share of tested buildings at or above 4 pCi/L runs from under 1% to over 80% across these Tampa Bay ZIP codes. Hillsborough's east side and Polk sit at the top of that range. The table below is that lookup, for 82 ZIPs, with the sample size next to the percentage. Test your own home either way.
82 ZIP codes
| 33563 | Plant City | Hillsborough | 132 | 66.7% | High (30%+) |
| 33616 | Tampa (Interbay / Port Tampa) | Hillsborough | 230 | 49.6% | High (30%+) |
| 33584 | Seffner | Hillsborough | 191 | 45% | High (30%+) |
| 33596 | Valrico | Hillsborough | 371 | 43.4% | High (30%+) |
| 33527 | Dover | Hillsborough | 65 | 41.5% | High (30%+) |
| 33510 | Brandon | Hillsborough | 608 | 41.1% | High (30%+) |
| 33594 | Valrico | Hillsborough | 2,803 | 34% | High (30%+) |
| 33602 | Tampa (Downtown) | Hillsborough | 253 | 17.8% | Elevated (15-29.9%) |
| 33547 | Lithia (FishHawk) | Hillsborough | 425 | 15.3% | Elevated (15-29.9%) |
| 33647 | Tampa (New Tampa) | Hillsborough | 1,862 | 14.7% | Moderate (5-14.9%) |
| 33565 | Plant City | Hillsborough | 55 | 14.5% | Moderate (5-14.9%) |
| 33566 | Plant City | Hillsborough | 86 | 14% | Moderate (5-14.9%) |
| 33615 | Tampa (Town 'n' Country) | Hillsborough | 506 | 13.6% | Moderate (5-14.9%) |
| 33511 | Brandon | Hillsborough | 1,148 | 13.4% | Moderate (5-14.9%) |
| 33567 | Plant City | Hillsborough | 175 | 13.1% | Moderate (5-14.9%) |
| 33578 | Riverview | Hillsborough | 406 | 12.8% | Moderate (5-14.9%) |
| 33635 | Tampa | Hillsborough | 234 | 12% | Moderate (5-14.9%) |
| 33611 | Tampa (South Tampa) | Hillsborough | 187 | 10.2% | Moderate (5-14.9%) |
| 33607 | Tampa | Hillsborough | 134 | 9.7% | Moderate (5-14.9%) |
| 33606 | Tampa (Hyde Park) | Hillsborough | 282 | 9.6% | Moderate (5-14.9%) |
| 33572 | Apollo Beach | Hillsborough | 124 | 8.9% | Moderate (5-14.9%) |
| 33569 | Riverview | Hillsborough | 625 | 7.7% | Moderate (5-14.9%) |
| 33573 | Sun City Center | Hillsborough | 66 | 7.6% | Moderate (5-14.9%) |
| 33624 | Tampa (Carrollwood area) | Hillsborough | 629 | 6.4% | Moderate (5-14.9%) |
| 33609 | Tampa | Hillsborough | 148 | 6.1% | Moderate (5-14.9%) |
| 33612 | Tampa | Hillsborough | 135 | 5.9% | Moderate (5-14.9%) |
| 33604 | Tampa | Hillsborough | 220 | 5% | Moderate (5-14.9%) |
| 33610 | Tampa | Hillsborough | 341 | 5% | Moderate (5-14.9%) |
| 33637 | Tampa | Hillsborough | 137 | 3.6% | Low (under 5%) |
| 33619 | Tampa | Hillsborough | 96 | 3.1% | Low (under 5%) |
| 33626 | Tampa (Westchase) | Hillsborough | 411 | 1.7% | Low (under 5%) |
| 33617 | Tampa (Temple Terrace area) | Hillsborough | 660 | 1.1% | Low (under 5%) |
| 33625 | Tampa | Hillsborough | 182 | 1.1% | Low (under 5%) |
| 33618 | Tampa (Carrollwood) | Hillsborough | 254 | 0.8% | Low (under 5%) |
| 33549 | Lutz | Hillsborough | 372 | 0.8% | Low (under 5%) |
| 33629 | Tampa (South Tampa) | Hillsborough | 358 | 0.6% | Low (under 5%) |
| 33614 | Tampa | Hillsborough | 798 | 0.3% | Low (under 5%) |
| 33613 | Tampa (USF area) | Hillsborough | 435 | ID | Insufficient data (FDOH shows ID) |
| 33634 | Tampa | Hillsborough | 67 | ID | Insufficient data (FDOH shows ID) |
| 33558 | Lutz | Hillsborough | 62 | ID | Insufficient data (FDOH shows ID) |
| 33556 | Odessa | Hillsborough/Pasco | 226 | ID | Insufficient data (FDOH shows ID) |
| 33761 | Clearwater | Pinellas | 253 | 23.7% | Elevated (15-29.9%) |
| 33716 | St. Petersburg | Pinellas | 458 | 19.4% | Elevated (15-29.9%) |
| 33702 | St. Petersburg | Pinellas | 156 | 15.4% | Elevated (15-29.9%) |
| 33711 | St. Petersburg | Pinellas | 72 | 12.5% | Moderate (5-14.9%) |
| 33762 | Clearwater | Pinellas | 90 | 11.1% | Moderate (5-14.9%) |
| 33760 | Clearwater | Pinellas | 124 | 10.5% | Moderate (5-14.9%) |
| 33774 | Largo | Pinellas | 58 | 10.3% | Moderate (5-14.9%) |
| 33770 | Largo | Pinellas | 51 | 7.8% | Moderate (5-14.9%) |
| 33764 | Clearwater | Pinellas | 87 | 6.9% | Moderate (5-14.9%) |
| 33759 | Clearwater | Pinellas | 478 | 4.8% | Low (under 5%) |
| 33704 | St. Petersburg | Pinellas | 60 | 3.3% | Low (under 5%) |
| 34685 | Palm Harbor | Pinellas | 319 | 2.8% | Low (under 5%) |
| 34695 | Safety Harbor | Pinellas | 123 | 2.4% | Low (under 5%) |
| 33701 | St. Petersburg (Downtown) | Pinellas | 108 | 1.9% | Low (under 5%) |
| 33756 | Clearwater | Pinellas | 65 | 1.5% | Low (under 5%) |
| 34683 | Palm Harbor | Pinellas | 169 | 1.2% | Low (under 5%) |
| 33782 | Pinellas Park | Pinellas | 88 | 1.1% | Low (under 5%) |
| 34684 | Palm Harbor | Pinellas | 203 | 1% | Low (under 5%) |
| 34689 | Tarpon Springs | Pinellas | 113 | 0.9% | Low (under 5%) |
| 33703 | St. Petersburg | Pinellas | 65 | ID | Insufficient data (FDOH shows ID) |
| 33765 | Clearwater | Pinellas | 72 | ID | Insufficient data (FDOH shows ID) |
| 33771 | Largo | Pinellas | 82 | ID | Insufficient data (FDOH shows ID) |
| 34698 | Dunedin | Pinellas | 65 | ID | Insufficient data (FDOH shows ID) |
| 33541 | Zephyrhills | Pasco | 92 | 5.4% | Moderate (5-14.9%) |
| 34668 | Port Richey | Pasco | 203 | 3% | Low (under 5%) |
| 33544 | Wesley Chapel | Pasco | 74 | 1.4% | Low (under 5%) |
| 34655 | New Port Richey | Pasco | 87 | 1.1% | Low (under 5%) |
| 34639 | Land O' Lakes | Pasco | 105 | 1% | Low (under 5%) |
| 33543 | Wesley Chapel | Pasco | 167 | 0.6% | Low (under 5%) |
| 33559 | Lutz | Pasco | 79 | ID | Insufficient data (FDOH shows ID) |
| 34667 | Hudson | Pasco | 109 | ID | Insufficient data (FDOH shows ID) |
| 33830 | Bartow | Polk | 159 | 83.6% | High (30%+) |
| 33801 | Lakeland | Polk | 67 | 37.3% | High (30%+) |
| 33813 | Lakeland | Polk | 622 | 33.9% | High (30%+) |
| 33860 | Mulberry | Polk | 51 | 29.4% | Elevated (15-29.9%) |
| 33811 | Lakeland | Polk | 170 | 24.7% | Elevated (15-29.9%) |
| 33805 | Lakeland | Polk | 278 | 24.1% | Elevated (15-29.9%) |
| 33803 | Lakeland | Polk | 569 | 23.7% | Elevated (15-29.9%) |
| 33810 | Lakeland | Polk | 87 | 19.5% | Elevated (15-29.9%) |
| 33884 | Winter Haven | Polk | 114 | 13.2% | Moderate (5-14.9%) |
| 33809 | Lakeland | Polk | 171 | 2.9% | Low (under 5%) |
No ZIP on this table matches that search.
Source: Florida Department of Health radon lookup, Certified Residential Database, data date February 21, 2019, retrieved October 22, 2026.Open the Department's lookup. We published ZIPs with at least 50 buildings tested. That cutoff is ours. The Department's tool also returns thinner ZIPs; we left 46 of those out of 128 checked. ID means the Department marked insufficient data, even though the building count cleared 50. Place names are our labels (a USPS city or a neighborhood) and are approximate. One row, 33556 Odessa, is stored as Hillsborough/Pasco because the ZIP crosses the county line.
What the percentage means (and doesn't)
It's the share of tested buildings over 4 pCi/L
Each percentage is buildings measured at or above 4 picocuries per liter, divided by buildings tested in that ZIP. The EPA action level is 4.0 pCi/L. The EPA also says to consider fixing a home between 2 and 4 pCi/L. How to read a single report is covered in what radon test results mean. The column is not an average pCi/L, and it is not a count of homes.
It's not a random survey
The Department's own lookup says this database is not a scientific or statistical survey. People who test are often in a real-estate deal, or they already suspect a problem. A ZIP where 34% of tested buildings were at or above 4 pCi/L is not the same sentence as "34% of homes there have radon."
Sample size matters
Valrico 33594 is 34% of 2,803 tested buildings. Dover 33527 is 41.5% of 65 tested buildings. The percentages are in the same band. The Valrico figure rests on a much larger pile of tests, so it moves less if a few unusual houses are in or out. A 65-building ZIP can print a high percentage from a short list. Read the buildings column before you rank two ZIPs.
Your house is not your ZIP
The Department puts it this way: locally, the number of homes reporting elevated radon varies from a high of 7 out of 10 to a low of 1 out of 100. Two houses on the same street can differ because of the slab, the additions, and the soil under that foundation. A low-percentage ZIP still contains homes over 4 pCi/L. A high-percentage ZIP still contains homes under it.
The highest-percentage ZIPs in Tampa Bay
These ten are the highest shares of tested buildings at or above 4 pCi/L in the 82-row table. The number in parentheses is buildings tested.
- 33830 Bartow: 83.6% (159 buildings), Polk County
- 33563 Plant City: 66.7% (132 buildings), Hillsborough County
- 33616 Tampa (Interbay / Port Tampa): 49.6% (230 buildings), Hillsborough County
- 33584 Seffner: 45% (191 buildings), Hillsborough County
- 33596 Valrico: 43.4% (371 buildings), Hillsborough County
- 33527 Dover: 41.5% (65 buildings), Hillsborough County
- 33510 Brandon: 41.1% (608 buildings), Hillsborough County
- 33801 Lakeland: 37.3% (67 buildings), Polk County
- 33594 Valrico: 34% (2,803 buildings), Hillsborough County
- 33813 Lakeland: 33.9% (622 buildings), Polk County
The cluster is eastern Hillsborough and Polk: Plant City, Seffner, Valrico, Dover, Brandon, then Bartow and Lakeland. That is the side of Tampa Bay nearest the phosphate district often called Bone Valley. The U.S. Geological Survey's geologic radon assessment for Florida, Open-File Report 93-292-D, is the study the EPA zone map points at for that geology (doi.org/10.3133/ofr93292D). Our geology guide explains the phosphate path in plain language. A high ZIP next to that district is not proof that phosphate caused that ZIP's tests. The table does not separate geology from who chose to test.
Where we have a city page, use it for the house, not just the rank: Tampa for 33616, Valrico for 33594 and 33596, and Brandon for 33510. Bartow, Lakeland, Plant City, Seffner, and Dover are in the table only.
County by county
Hillsborough County
37 Hillsborough ZIPs have a published percentage, from 0.3% in 33614 (798 buildings) to 66.7% in 33563 (132 buildings). 3 more Hillsborough rows are ID. The EPA Florida map puts Hillsborough in Zone 2. The same map puts no Florida county in Zone 1.
City pages for this county: Tampa, Brandon, Riverview, South Tampa, Carrollwood, Temple Terrace, Lutz, and Valrico. The longer county article is radon in Hillsborough County.
Pinellas County
19 Pinellas ZIPs have a percentage, from 0.9% in 34689 (Tarpon Springs) to 23.7% in 33761 (Clearwater, 253 buildings). 4 Pinellas rows are ID. Pinellas is EPA Zone 3, the lower band on that 1993 map, and several ZIPs are still in double digits. Zone 3 is not a reason to skip a test. Read radon in Pinellas and Pasco, then the city pages for St. Petersburg and Clearwater.
Pasco County
6 Pasco ZIPs have a percentage, from 0.6% in 33543 to 5.4% in 33541 (Zephyrhills). 2 more are ID. Pasco is EPA Zone 3. The city page we publish there is Wesley Chapel, which covers 33543 (0.6% of 167 buildings) and 33544 (1.4% of 74).
Polk County (Lakeland, Bartow)
10 Polk ZIPs are in the table, from 2.9% in 33809 (Lakeland) to 83.6% in 33830 (Bartow, 159 buildings). Polk is EPA Zone 2, the same band as Hillsborough. Bartow 33830 is the highest percentage in the whole Tampa Bay file. We included Polk because the Department's release covers it and because dropping it would hide the top of the range. This site does not have a Polk service page, and this section is not a quote button for Lakeland or Bartow. Quote requests we route are the cities under service areas in Hillsborough, Pinellas, and Pasco.
33556 Odessa is the one split-county row (Hillsborough/Pasco). The Department marked it ID after 226 buildings tested.
EPA radon zones for Tampa Bay counties
The EPA Map of Radon Zones is a 1993 county map, not a ZIP map. On the Florida sheet, Hillsborough and Polk are orange (Zone 2) and Pinellas and Pasco are yellow (Zone 3). Florida has no Zone 1 county. A secondary count of that same map lists 9 Zone 2 counties, 58 Zone 3 counties, and 0 Zone 1 counties. The EPA sheet is the primary source: Florida radon zone map (PDF) and the EPA map overview. Some local writeups call Hillsborough or Pinellas Zone 1. That does not match this map.
| County | EPA zone | On the Florida map |
|---|---|---|
| Hillsborough | Zone 2 | Orange, moderate |
| Polk | Zone 2 | Orange, moderate |
| Pinellas | Zone 3 | Yellow, lower |
| Pasco | Zone 3 | Yellow, lower |
The EPA's line on the map is direct: all homes should be tested, regardless of zone designation. The same page says the map should not be used to determine if a specific home needs to be tested. Zone 2 is not "high," and Zone 3 is not "none."
What to do with your ZIP's number
High or Elevated on this table means test now if you have not. If you are buying, test during the inspection period, not the week of closing. How testing works and the radon contingency guide cover the clock. A real-estate test still needs time under closed-house conditions.
Low band means test once anyway. If a short-term result is under 4 pCi/L, the Department says to keep testing the home every 2 years. The low ZIP did not measure your slab.
If a test is over 4 pCi/L, follow the Department's follow-up rules before you treat one short test as the whole story. At 8 pCi/L or more on a short-term test, the Department suggests a second test of the same length in the same place, then an average. Between 4 and 8, it says to choose a short-term or a long-term follow-up, and it prefers the long-term test, which runs over 91 days. If the follow-up is still over 4, talk with a certified mitigator. What mitigation involves and the mitigation cost guide are the next pages. What a radon test costs is the testing price page, separate from the system price.
The Department also offers radon test kits through a request form. We checked that form on October 22, 2026: the page titled Radon Testing Kit Request was up, the nav calls it a free kit, and the instructions say to mail the kit back close to 48 hours after you start it. A kit not returned within three months of receipt is not analyzed. Confirm the form is still open before you rely on it: Florida radon test kit request.
Get a free radon quote if you want a certified test or a mitigation conversation. We connect you with local professionals. We do not test the house or install the system.
How we built this table
On October 22, 2026 we queried the Department's ZIP lookup one ZIP at a time across Tampa Bay. The tool's source file covers more ZIPs than this page. We checked 128 and omitted 46 with fewer than 50 buildings tested. That threshold is an editorial choice so a tiny sample is not ranked next to a ZIP with thousands of tests. Rows the Department marked ID stayed in, as long as the building count was at least 50. Nothing here was re-estimated, smoothed, or filled in. If the Department updates the Certified Residential Database, we will replace this file and change the data date. Until then the release date remains February 21, 2019.
Updated October 22, 2026. Radon Mitigation Tampa is a referral service. A quote request may be shared with up to a few local radon professionals, who may contact you by phone, text, or email.
Questions about ZIP-level radon data
How do I find radon levels for my ZIP code in Florida?
Use the table on this page. It lists 82 Tampa Bay ZIP codes from the Florida Department of Health Certified Residential Database, released February 21, 2019, and retrieved October 22, 2026. You can also search up to five ZIPs at a time on the Department's own lookup. Then test the house. A ZIP percentage is not a reading for one address.
Which Tampa Bay ZIP codes have the highest radon?
By the share of tested buildings at or above 4 pCi/L: Bartow 33830 (83.6% of 159), Plant City 33563 (66.7% of 132), Tampa Interbay / Port Tampa 33616 (49.6% of 230), Seffner 33584 (45% of 191), Valrico 33596 (43.4% of 371), Dover 33527 (41.5% of 65), Brandon 33510 (41.1% of 608), Lakeland 33801 (37.3% of 67), Valrico 33594 (34% of 2,803), and Lakeland 33813 (33.9% of 622).
Is Hillsborough County a high radon zone?
On the EPA Map of Radon Zones for Florida, Hillsborough County is Zone 2, the moderate band. Polk County is also Zone 2. Pinellas and Pasco are Zone 3. No Florida county is Zone 1. The map dates from 1993, and the EPA says it should not be used to decide whether an individual home needs a test.
If my ZIP is low, do I still need to test?
Yes. The Florida Department of Health says the only way to tell if a home has a radon problem is to test it, and that locally the number of homes reporting elevated radon varies from 7 out of 10 to 1 out of 100. The EPA says all homes should be tested, regardless of zone.
How current is this data?
The Florida Department of Health labels this Certified Residential Database release February 21, 2019. We retrieved the 82 ZIP rows on October 22, 2026. We will re-pull the table when the Department publishes a newer release.
What does ID mean in the radon ZIP table?
ID is the Florida Department of Health flag for insufficient data. These 10 rows still had at least 50 buildings tested, which is our cutoff for publishing a ZIP, but the Department did not publish a percentage.
Is radon testing required in Florida?
There is no statute that makes every homeowner test. Florida Statute 404.056(5) requires a radon notification, in specified language, on at least one document executed at the time of or before a contract for sale and purchase of any building, or a rental agreement for any building. A residential transient stay of 45 days or less is excluded. A different subsection, 404.056(4), requires radon measurement in certain schools, 24-hour care facilities, and licensed day care centers in counties the state's radon-protection map marks as intermediate or elevated potential. That is not a test of every house. See the Florida radon disclosure guide for the notice wording.
The notice required on Florida sale contracts and many leases is quoted on our disclosure-law page, checked against section 404.056(5) of the 2025 Florida Statutes. The testing decision is still yours. Request a quote when you want a person to schedule it.
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