Gonorrhea cases in San Mateo County run about 30% lower than the US average. Whether you need a one-time concern or regular check-ups in San Mateo County, California, you can choose between walk-in clinics for same-day testing or labs and at-home kits to fit your schedule.
Available testing centers
12 testing options are listed for San Mateo, CA. The nearest, Central County Mental Health CTR, is about 0.7 miles away. Compare community and public clinics, private labs, and at-home kits below.
Listings tagged Community health center are federally funded health centers and rural clinics that treat everyone regardless of insurance or ability to pay: required to bill on a sliding fee scale and provide confidential care, and in many states minors may consent to their own STI testing. A Title X tag flags centers funded for confidential family-planning services; confirm current participation when you call.
Source: CMS FQHC & Rural Health Clinic enrollment files (data.cms.gov), refreshed quarterly. Title X status reflects the latest OPA grantee list.
Central County Mental Health CTR, serving San Mateo, carries federal qualification that requires sliding-scale fees tied to income. Meaning cost adjusts to what a patient actually earns. Walk-in STI screening covers syphilis, gonorrhea, and chlamydia without an appointment needed.
Tests offered
Fees & payment
Stanford Children's Health in San Mateo requires an appointment and covers gonorrhea, chlamydia, syphilis, HIV, herpes, hepatitis A, B, and C, and TB on a sliding-scale fee basis, with same-visit treatment for bacterial infections and insurance or Medicaid accepted.
Prevention-only clinics often hand off prescription-based HIV prevention entirely. Stanford Children's Health in San Mateo writes both PrEP and PEP in-house, meaning the clinical relationship that begins with testing can extend directly into ongoing or emergency prevention without switching providers.
The panel at Stanford Children's Health in San Mateo includes herpes simplex and hepatitis A, B, and C alongside the standard bacterial and HIV tests: infections screened in a single appointment, each with its own clinical consequence for treatment or vaccination eligibility.
Languages
English
Tests offered
Serves
Care services
Prevention services
Fees & payment
Listing verified Dec 2025 · Source: CDC NPIN
North East Medical Services - 35 Baywood, San Mateo, welcomes walk-ins for STI screening without an appointment. Federal qualification anchors its sliding-scale fee structure, making syphilis, gonorrhea, and chlamydia testing available at costs tied to household income, so a single visit can cover the full standard panel.
Tests offered
Fees & payment
HealthRIGHT360–San Mateo Clinic serves anyone navigating care without insurance or on a tight budget, meeting them with federally qualified sliding-scale fees tied to income. Walk-ins are welcome for syphilis, gonorrhea, and chlamydia screening: no appointment needed, no fixed price standing between someone and testing.
Tests offered
Fees & payment
County of San Mateo Health System in San Mateo covers HIV, syphilis, gonorrhea, chlamydia, and hepatitis testing alongside same-visit treatment for bacterial infections. All at no fee, on a sliding scale that reaches zero. Appointments are required.
The no-fee structure here applies across the entire menu (testing, PrEP initiation, mpox vaccination, and HIV prevention education) not to a subset of services. That universality means no appointment ends with an unexpected charge for a component that fell outside a waived category.
Spanish is a direct clinical language at County of San Mateo Health System, covering everything from PrEP counseling to HIV prevention education. Care conducted in a patient's primary language reduces the chance of dosing details or follow-up instructions getting lost in translation.
Many clinics deliver an HIV-positive result and hand off ongoing management elsewhere. Ryan White funding at County of San Mateo Health System closes that gap, the same facility that handles testing also carries patients through treatment, so HIV care remains continuous rather than fractured across providers.
Languages
English, Spanish
Tests offered
Serves
Care services
Prevention services
Fees & payment
Listing verified Apr 2026 · Source: CDC NPIN + HRSA
San Mateo County Health Department runs on scheduled appointments, so every visit is purpose-built: gonorrhea, chlamydia, syphilis, herpes, and rapid or conventional HIV testing, plus same-visit treatment for bacterial infections, all provided at no charge.
The clinic is staffed and budgeted to absorb the full cost of every service (testing, treatment, vaccines, and PrEP) so sliding scale means the floor is zero and nothing is withheld. No co-pay tier, no billing step at checkout.
Clinical staff provide care directly in Spanish, which means a patient's history, treatment plan, and follow-up instructions are discussed and understood in the same conversation. Reducing the gap between what is said and what is acted on.
Many STI testing sites screen for HIV but stop short of prescribing the medications that prevent it: San Mateo County Health Department carries both PrEP and PEP as active clinical services, with prescribing and monitoring handled by its own staff.
Languages
English, Spanish
Tests offered
Serves
Care services
Prevention services
Fees & payment
Listing verified Aug 2025 · Source: CDC NPIN
NEMS Administrative Building - Gilbreth, in Burlingame, earned federal qualification precisely so people paying out of pocket, between insurance plans, or living on modest incomes have a real clinical option. Fees slide with income, and standard STI screening covers syphilis, gonorrhea, and chlamydia. No appointment needed.
Tests offered
Fees & payment
Canyon Vista in Redwood City welcomes walk-ins for STI screening without an appointment. Federally qualified status ties fees to a sliding scale based on income, and a single visit can cover syphilis, gonorrhea, and chlamydia testing in one stop.
Tests offered
Fees & payment
Free tool · not a clinic
Testing too soon can miss an infection. Enter the date of possible exposure to see the earliest a test can reliably detect each STI.
| Infection | Earliest reliable test | Conclusive after |
|---|---|---|
| Chlamydia | 7 days after exposure | 14 days after exposure |
| Gonorrhea | 7 days after exposure | 14 days after exposure |
| Trichomoniasis | 7 days after exposure | 28 days after exposure |
| HIV (NAT / RNA) | 10 days after exposure | 33 days after exposure |
| HIV (4th-gen Ag/Ab) | 18 days after exposure | 45 days after exposure |
| HIV (antibody) | 21 days after exposure | 84 days after exposure |
| Syphilis | 21 days after exposure | 42 days after exposure |
| Hepatitis B | 21 days after exposure | 42 days after exposure |
| Hepatitis C | 56 days after exposure | 77 days after exposure |
| Herpes (HSV) | 28 days after exposure | 112 days after exposure |
Guidance only, confirm timing with a clinician. A negative result before the conclusive date may need a repeat test.
Typical out-of-pocket ranges by option, actual cost depends on which tests you need.
Public / community clinic
Free HIV testing is common
Private lab (self-pay)
Never billed to insurance
At-home kit
Mailed to your door, private
Doctor / urgent care
Often $0 preventive with insurance
No centers match those filters. Clear the service-type filter or the opening-hours filters to see every center.
Every other option
Beyond the dedicated testing centers above: at-home kits by mail, hospital labs certified for STI testing, local clinicians who can order a panel during a regular visit, pharmacies for self-test kits and prescriptions, and online PrEP & treatment.
Test from home
The nearest testing center is less than a mile away; if you'd rather skip the trip, an at-home kit ships to San Mateo, you collect the sample privately, and mail it back to a CLIA-certified lab. Results come online in days, with a clinician available if anything is positive. Same labs as a clinic, no waiting room, and you can read how accurate at-home STD tests are before you order.
Want a free option first? The CDC-supported TakeMeHome (opens in a new tab) program mails free at-home HIV self-test kits, and, in many areas, free STI kits, to your door, with no insurance or payment needed. The paid kits below add broader panels and faster turnaround.
In-home collection
$79 & up
Best value: single tests
$49 & up
Best range: couples & full panels
$79 & up
Every kit uses CLIA-certified labs. At-home testing is for screening; a reactive result should be confirmed and treated by a clinician. Prices and panels shown are illustrative and change often, confirm current details on the provider's site.
Also in the area
Beyond the public testing sites above, these federally certified (CLIA) labs serve San Mateo County, each lab's town is shown on its card below. Many test through a doctor's order or by appointment rather than walk-in, so call ahead to confirm STD/STI testing and availability before visiting.
353 Hatch Drive, Foster City, CA 94404
CMS-certified lab Accredited · College of American Pathologists
1900 Alameda De Las Pulgas Suite 100, San Mateo, CA 94403
CMS-certified lab Accredited · College of American Pathologists
100 So San Mateo Drive, San Mateo, CA 94401
CMS-certified lab Accredited · College of American Pathologists
500 Lincoln Centre Drive, Foster City, CA 94404
CMS-certified lab Accredited · College of American Pathologists
1241 East Hillsdale Boulevard, Suite 100, Foster City, CA 94404
CMS-certified lab
Showing the nearest 5 CLIA-certified labs.
Source: CMS CLIA registry (Provider of Services), Q1 2026. Federal public records: active CLIA-certified laboratories near San Mateo. A CLIA certificate records only that a laboratory is federally certified — it does not confirm the site performs STD testing, nor its hours, price or access. Inclusion is not an endorsement; always call to verify.
Local clinicians
Beyond dedicated clinics, 5,640 primary-care, OB-GYN, infectious-disease and other clinicians have a CMS practice record within 30 miles of San Mateo. They may be able to evaluate symptoms or order a confidential STD panel during a regular visit, and 2,370 offer telehealth.
June-Ho Kim, MD Telehealth
Internal medicine · 2950 South Delaware Street, San Mateo
Mohammed Bailony, MD Telehealth
Internal medicine · 3050 South Delaware Street, San Mateo
Aaron Roland, MD
Family medicine · 3050 South Delaware Street, San Mateo
John Cunniff, MD
Internal medicine · 123 South San Mateo Drive, San Mateo
John Chow, MD Telehealth
Internal medicine · 101 South San Mateo Drive, San Mateo
Gayathri Thirumalaiselvan, MD Telehealth
Internal medicine · 101 South San Mateo Drive, San Mateo
These are registry-listed clinicians, not dedicated STD-testing clinics. CMS records do not independently verify current licensure, testing services, availability, price, or new-patient status. Confirm each detail before booking. Source: CMS Doctors & Clinicians.
Nearby pharmacies
No pharmacy near San Mateo, CA publishes an STD-related service or holds a current CLIA testing certificate, so these are simply the closest. Contact a location directly to confirm counter hours, services, prices, and availability before visiting.
0.1 mi 
0.2 mi 
0.5 mi Ted's Village Pharmacy
0.7 miShowing the 4 closest pharmacies to San Mateo, CA.
Directory records identify nearby pharmacies. Service, stock, price, and hours information is shown only when supported by current location-specific evidence.
Prevention & treatment
Testing is one step. For residents of San Mateo, telehealth covers the rest: HIV-prevention medication (PrEP) and DoxyPEP to lower future risk, and discreet online treatment if a result comes back positive. All prescribed by licensed U.S. clinicians.
Visit from $0 insured
Telehealth STI treatment and sexual-health care, delivered or to your pharmacy
Visit from $39
Online STI treatment & DoxyPEP: same-day prescriptions to your pharmacy
$0 with most insurance
Free online PrEP & DoxyPEP: HIV prevention, home lab kits, no in-person visit
From $0 insured
Telehealth PrEP & DoxyPEP with at-home testing and ongoing monitoring
Pricing varies by insurance and changes often, confirm on the provider's site. These services are not a substitute for emergency care.
STD stats & rates
How reported STI rates in San Mateo County, the county that includes San Mateo, compare with California and U.S. averages, based on the most recent 2023 surveillance data. An estimated ~28% of residents are aged 15–34 (ACS), the age group with the highest reported chlamydia and gonorrhea rates nationally.
#26 of 58 California counties for chlamydia, a higher rate than 55% of the state
| Infection | San Mateo County | California | United States |
|---|---|---|---|
| Chlamydia | 360.4 2,618 cases ▼ 27% | 491.1 | 492.2 |
| Gonorrhea | 125.3 910 cases ▼ 34% | 190.2 | 179.5 |
| Syphilis (P&S) | 9.2 67 cases ▼ 44% | 16.3 | 15.8 |
| Syphilis (early) | 11.6 84 cases ▼ 39% | 19.1 | 16 |
| Syphilis (late/unknown) | 19.1 139 cases ▼ 59% | 46.7 | 29.5 |
Rates per 100,000 population, 2023. Source: CDC NCHHSTP AtlasPlus (county, state & U.S., all-ages basis). Population figures: U.S. Census Bureau ACS. These figures are the latest available surveillance estimates. Bars are scaled to the highest rate shown.
Reading these numbers: reported case rates only count infections that were actually tested for and diagnosed, so they track local screening effort as much as true spread: a higher rate can reflect more testing, a lower one less. Either way, most STIs cause no symptoms, so treat the figures above as context rather than a verdict, and test on the CDC's schedule regardless of how your area looks.
Between 2020 and 2023 in San Mateo County, chlamydia has risen from 263.1 to 360.4 per 100,000 (37%), gonorrhea has risen from 108.3 to 125.3 per 100,000 (16%), and P&S syphilis has fallen from 12.3 to 9.2 per 100,000 (25%).
The 2020 dip reflects reduced pandemic-era screening, not lower transmission. Source: CDC NCHHSTP AtlasPlus (county, state & U.S., all-ages basis).
Community health context
Sources: CDC PLACES (ZIP), County Health Rankings, CDC/ATSDR SVI, HRSA HPSA, HRSA MUA/P, Neighborhood Atlas ADI. Lower insurance coverage, fewer routine checkups, and a thin primary-care ratio all raise the value of low-cost public clinics and at-home testing in San Mateo County.
Local HIV snapshot
San Mateo County HIV care continuum (2023)
San Mateo County recorded 12.2 new HIV diagnoses per 100,000 (2023), against 14.9 statewide and 13.7 nationally. Among San Mateo County residents living with HIV, 75.4% are in care · 55.4% are virally suppressed. Early, routine testing is what moves these numbers: it is the entry point to PrEP, treatment, and viral suppression.
Sources: AIDSVu (Emory/Gilead) · CDC AHEAD · CDC AtlasPlus · CDC NCHHSTP AtlasPlus (county care continuum). The CDC recommends everyone aged 13–64 test for HIV at least once: every lab and clinic listed above offers HIV testing, and free rapid HIV testing is available at a local health department.
Congenital syphilis, passed from parent to baby in pregnancy, is the fastest-rising STI in the country. U.S. cases climbed from 2,163 in 2020 to 3,882 in 2023. It is almost entirely preventable: the CDC recommends a syphilis test at the first prenatal visit, and every clinic and lab listed for San Mateo County tests for syphilis.
Source: CDC NCHHSTP AtlasPlus, 2023 (county-level congenital syphilis is not published).
Local resources & officials
Data & references
Local context
Devonshire runs quieter than the commercial corridors along CA 82, and the households there reflect something true of San Mateo broadly: most residents are working, many are partnered, and the days fill up fast. With nearly three quarters of adults in the labor force and unemployment sitting low, the city hums on packed schedules, which is exactly when a routine screening appointment is easiest to skip. That pressure lands unevenly on younger adults in their late teens and twenties, the years when new sexual partnerships are most common and when STI transmission runs highest.
San Mateo's share of residents in that window is substantial, and the cost environment adds its own weight: typical monthly rent here clears two thousand dollars, meaning time off work carries a real dollar cost that shapes how people weigh any errand that isn't urgent. Even among households that clear six figures, a surprising share of them, more than half of San Mateo residents live in that range, discretionary spending on health visits can still feel squeezed by Bay Area overhead. For someone based near Foster City or commuting through the CA 92 interchange, the range of listed clinics means the right appointment is likely a short drive rather than a half-day detour.
Getting there
San Mateo scores 10.83/20 on the EPA walkability index, so many trips are walkable or a short ride, though a car still gives you the widest choice of testing centers.
Source: EPA National Walkability Index 2021.
ZIP 94403 snapshot
ZIP-level Census figures for the wider 94403 area around San Mateo: a single ZIP can span several communities, so they describe the area, not San Mateo alone.
San Mateo sits in San Mateo County, ZIP 94403. Local context that shapes where residents test:
Local landmarks
Neighborhoods & communities
Major routes
Nearby cities & towns
Just outside San Mateo? These nearby communities have their own testing guides: clinics, at-home kits, and free screening close to home.
Reference
Everything to know before you test in San Mateo County: the CDC's screening guidelines, each infection's detection window, per-test reference prices, and your privacy rights under California law. If you have symptoms right now, our confidential symptom checker maps them to the tests worth considering.
Based on current CDC screening recommendations.
| Group | Tests | How often |
|---|---|---|
| Everyone aged 13–64 | HIV | At least once |
| Sexually active women under 25 | Chlamydia, gonorrhea | Every year |
| Women 25+ with new or multiple partners | Chlamydia, gonorrhea | Every year |
| Pregnant people | HIV, syphilis, hepatitis B & C, chlamydia | Early in pregnancy |
| Gay & bisexual men (MSM) | Chlamydia, gonorrhea, syphilis, HIV | Every 3–6 months |
| Anyone who shares injection equipment | HIV, hepatitis B & C | At least yearly |
| All adults at least once | Hepatitis C | At least once |
Testing too early can return a false negative, confirm timing with a San Mateo-area provider.
| Infection | Earliest reliable test | Sample |
|---|---|---|
| Chlamydia | 1–2 weeks | Urine or swab |
| Gonorrhea | 1–2 weeks | Urine or swab |
| Trichomoniasis | 1–4 weeks | Urine or swab |
| HIV (NAT / RNA) | 10–33 days | Blood |
| HIV (4th-gen Ag/Ab) | 18–45 days | Blood |
| HIV (antibody) | 3–12 weeks | Blood / oral |
| Syphilis | 3–6 weeks | Blood |
| Hepatitis B | 3–6 weeks | Blood |
| Hepatitis C | 8–11 weeks | Blood |
| Herpes (HSV) | 4–16 weeks (antibody); swab a sore | Blood / swab |
These are the federal Medicare reference prices for processing each lab test. Public clinics and the community health centers serving San Mateo often test free or on a sliding scale; private labs and at-home kits bundle several tests into one fee. Use this as a per-test benchmark before you pay out of pocket, or see the full guide to STD test costs for insurance, free, and at-home options.
| Test | Reference price | CPT / HCPCS |
|---|---|---|
| Chlamydia (NAAT) | $47.80 | 87491 |
| Gonorrhea (NAAT) | $47.80 | 87591 |
| Trichomoniasis (NAAT) | $47.76 | 87661 |
| HIV-1/2 antigen/antibody | $26.87 | 87389 |
| HIV-1/2 antibody | $22.44 | 86703 |
| Syphilis (RPR/VDRL) | $5.61 | 86592 |
| Syphilis (treponemal antibody) | $17.49 | 86780 |
| Herpes (HSV NAAT) | $47.76 | 87529 |
| Hepatitis B surface antigen | $15.33 | 87340 |
| Hepatitis C antibody | $29.16 | 86803 |
Source: Medicare Clinical Laboratory Fee Schedule, CMS, 2025 rates (data.cms.gov). Reference rate for the lab assay only: a clinic visit, sample collection, or a bundled multi-test panel may cost more. Medicaid and most insurers cover STD screening at no out-of-pocket cost.
Two things that actually depend on California law: who can consent, and whether partners can be treated without their own visit. Everything else about testing privately is the same nationwide (see below).
In California, a minor aged 12 or older can consent to confidential STI testing and treatment on their own, no parental permission is required.
California permits Expedited Partner Therapy (EPT): if you test positive for chlamydia or gonorrhea, your provider can give you medication (or a prescription) to pass to your partner, no separate exam or appointment needed for them.
Keeping a test private works the same in every state. Whether an STD test shows on insurance (the EOB), how to test anonymously, and self-pay options that leave no insurance trail don’t change by location.
Learn more about confidential STD testing in CaliforniaSource: Guttmacher Institute, Minors' Access to STI Services; CDC, Legal Status of Expedited Partner Therapy. General information, not legal advice.
Good to Know
Answers to the questions people ask most before getting tested.
Possibly, Redwood City, CA is close; compare it by distance against Central County Mental Health CTR.
Public clinics are free; private labs ~$24–$139, at-home kits $49+.
Public clinics nearby offer free HIV testing.
Local options test for Chlamydia, Gonorrhea, Syphilis, Herpes, Hepatitis A, Hepatitis B, Hepatitis C, Rapid HIV, a full panel covers the common ones.
About 360 cases per 100,000 residents (2023), below the California average.
In California, people under 18 can consent to confidential STD testing and treatment on their own.
PrEP (HIV-prevention medicine for HIV-negative people) is available locally, any provider can prescribe it.
Lab results typically come back in 1–2 days.
Expedited partner therapy lets a provider treat a partner without an exam, where state law allows.
Just note your exposure dates and symptoms; for urine tests, hold off urinating ~1 hour before.
Have a different question? Browse the full STD & STI FAQ library, every question we answer, in one place.