How to Become an Associate Certified Entomologist (ACE): The Complete Guide

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Part of our entomology certification hub comparing the ACE, PHE, and BCE credentials.

Going further? The Board Certified Entomologist (BCE) is the top credential in entomology — see the guide and free BCE practice exams.

Working in public health or vector control? The ESA also offers the Public Health Entomology (PHE) Certificate — see our guide and free PHE practice exam.

Everything a working pest management professional needs to know to earn the Associate Certified Entomologist (ACE) credential — the requirements, the exam, the complete pest list, and how to actually pass — written by an ACE who has been through it. This is the long version. Nothing here is summarized.

What is an Associate Certified Entomologist (ACE)?

The ACE is a professional certification administered by the ESA Certification Corporation, the certification arm of the Entomological Society of America (ESA) in Annapolis, Maryland. It was designed specifically for professionals whose entomology training came through continuing education, self-study, and on-the-job experience rather than a university degree. In ESA’s own words, it exists so that a skilled pest management professional can prove entomological competence to employers and customers the same way a licensed doctor, lawyer, or building inspector proves theirs.

An ACE is not a hobbyist who took a quiz. It is a credential that verifies you can inspect, correctly identify pests, understand their biology, choose and implement control methods responsibly under an Integrated Pest Management (IPM) framework, and follow a formal Code of Ethics.

ACE vs. BCE vs. CIT vs. PHE: the ESA credential landscape

ESA offers four professional credentials. Choosing the right one matters:

• ACE (Associate Certified Entomologist) — for practicing pest management professionals; no degree required. The focus is structural and urban pest management.
• BCE (Board Certified Entomologist) — for degreed entomologists (a bachelor’s or higher in a biological/life science with at least four term-length entomology courses). Broader scope, with specialty categories.
• CIT (Certified IPM Technician) — entry-level (1–4 years of experience), focused on IPM for common household pests.
• PHE (Public Health Entomology) — for professionals working with disease vectors and pests posing public-health risks (5+ years).

The core difference between the two most sought-after credentials is simple: the BCE requires a degree; the ACE recognizes experience. If you have built real expertise in the field over years of practice, the ACE is your path to formal recognition.

Why the ACE credential matters

In an industry with heavy competition and low barriers to entry, the ACE is a genuine differentiator. It signals to customers and employers that the person diagnosing their problem actually understands the science — the biology, the identification, the reasons a treatment works or fails. ESA positions it as a way to earn better visibility, opportunities, and jobs, and it is recognized by third parties, including the U.S. Department of Defense’s COOL (Credentialing Opportunities On-Line) program. In practice, an ACE is trusted with the cases other technicians can’t solve — the recurring infestations, the misidentifications, and the situations where the answer isn’t a spray at all.

Eligibility requirements (exact)

For a U.S. applicant without an academic entomology degree, you need all of the following:

• A current pesticide applicator’s license or certificate (U.S. state, military, territorial, or tribal) that allows you to apply pesticides in an urban, industrial, or structural setting without supervision, and that requires continuing education to remain current. (If your state doesn’t require ongoing education for the license, you’re exempt from that portion.)
• A minimum of 5 years of verifiable pest management experience in the United States, documented by a résumé, CV, or an employer’s attestation of employment.
• Two letters of professional reference from employers, major clients, or colleagues who can speak to your professionalism, entomological knowledge, and ethics.
• The application fee (which includes your first year of certification and the exam).
• Agreement to adhere to the ACE Code of Ethics.
• And, of course, the ability to pass the exam.

Education substitutions reduce the experience requirement (submit transcripts with your application):

• Bachelor’s in entomology or a related life science → 3 years of post-degree experience.
• Master’s → 2 years.
• PhD → 1 year.

Non-U.S. applicants (ACE-International): the requirements are the same except no pesticide license is required — instead you take and pass a second exam on pesticide safety.

The application process, step by step

1. Gather your documents in digital form: a copy of your applicator’s license and your two reference letters.
2. Submit the ACE application through your ESA account.
3. ESA staff review the application; on approval you receive an approval email.
4. From the approval date, you have one year to take and pass the exam, or the application expires.
5. Schedule your exam through your ESA account. As of 2026, exams are proctored remotely through ProctorU.

The ACE examination (exact)

• Format: closed-book, online, remotely proctored (ProctorU).
• Length: 150 questions (multiple-choice and true/false), one sitting of 3 hours or less.
• Passing score: 75%, scored immediately by the software.
• Retakes: allowed no sooner than 30 days and no later than 365 days after a prior attempt. Your first two attempts are covered by the application fee; additional attempts are $75 ($50 for ESA members). You must pass within one year of application approval.
• ESA offers a free sample exam to gauge readiness, and recommends a minimum of 40 hours of self-study regardless of experience — this is not an exam you can cram for.

The four exam domains (and how much each counts)

Every question maps to one of four domains. Weight your studying accordingly:

• Domain 1 — Inspection & Identification (45%). The single largest block. Inspecting for pest evidence (damage, frass, egg types) and conducive conditions using tools like flashlights, moisture meters, and flushing agents; and identifying pests by taxonomy, morphology, and biology (physiology, behavior, habitat, life cycle, reproductive potential, and the damage they cause). Plus documenting findings, thresholds, and the Code of Ethics.
• Domain 2 — Monitoring (12%). Selecting and placing monitoring tools (light traps, pheromone traps, glueboards). The pests most commonly monitored are cockroaches, flies, stored-product pests, termites, and bed bugs.
• Domain 3 — Selection & Implementation of Control Methods (28%). Cultural, biological, mechanical, and chemical control and their trade-offs; pesticide modes of action, classifications, resistance, formulations, and application; reading and following labels; FIFRA and EPA’s role; state vs. federal authority; and the historical/banned chemistries (DDT, chlordane, lindane; carbamates; organophosphates). The guiding principle is the least-hazardous effective method.
• Domain 4 — Evaluation (15%). Verifying pest reduction, analyzing pre/post-treatment results, thresholds, resistance, and determining the next IPM steps — with documentation and audit awareness.

Together, Domains 1 and 3 make up 73% of the exam. Pest identification and control decision-making are where the test lives.

Cost and timeline

• Application fee: $395 (non-member) / $355 (ESA member) — includes your first year of certification and the exam (first two attempts).
• Additional exam attempts: $75 / $50 member.
• Timeline: application review → approval → up to one year to study and pass. The exam is scored immediately; passing earns you a digital credential and a mailed welcome kit.

Keeping your ACE: renewal and maintenance

• Renewal cycle: every 3 years (no retesting required).
• Continuing education: document a minimum of 18 CEUs over the 3-year period (often the same credits you use to renew your applicator’s license), plus a current license copy and a signed Code of Ethics statement.
• Renewal fee: $375 / $295 member.
• Inactive status: available if you temporarily leave the industry — up to 2 consecutive years, after which you reactivate or lose the credential.
• Emeritus status: for those who have held the ACE at least 7 years and retired — half fees, no license or CEUs required.

The complete ACE pest list — all 8 sections, ~130 pests

Section 1 — Biting & Stinging Pests

The largest and highest-yield section. It blends medically important arthropods (bed bugs, mosquitoes, ticks, lice, mites, spiders) with stinging Hymenoptera (wasps, bees, hornets).

• Bed bugs & bat bugs — Cimex spp.
• Yellowjacket wasps — Vespula, Paravespula, and Dolichovespula maculata (bald-faced hornet)
• Paper wasps — Polistes spp.
• Mosquitoes — family Culicidae
• Honey bee — Apis mellifera
• Black widow spiders — Latrodectus spp.
• Brown recluse spiders — Loxosceles spp.
• European hornet — Vespa crabro
• Cat flea (representing fleas) — order Siphonaptera
• Brown dog tick — Rhipicephalus sanguineus
• American dog tick — Dermacentor variabilis
• Scorpions — order Scorpiones
• Wolf spiders — family Lycosidae
• Bumble bees — Bombus spp.
• Black-legged (deer) tick — Ixodes spp.
• Solitary bees — families Apidae, Andrenidae, Megachilidae, Halictidae, Colletidae
• Flesh flies — family Sarcophagidae
• Stable fly — Stomoxys calcitrans
• Rodent and bird mites
• Black & yellow mud dauber — Sceliphron spp.
• Lone star tick — Amblyomma americanum
• Sac spiders — family Miturgidae (incl. Cheiracanthium)
• Hobo & funnel-weaver spiders — family Agelenidae
• Soft ticks — family Argasidae
• Cicada killer — Sphecius speciosus
• Ground spiders — family Gnaphosidae
• Jumping spiders — family Salticidae
• Organpipe mud dauber — Trypoxylon spp.
• Head louse — Pediculus humanus capitis
• Dust mites — Dermatophagoides spp.
• Body louse — Pediculus humanus humanus
• Crab louse — Pthirus pubis
• Chigger mites — family Trombiculidae

Section 2 — Flies (Order Diptera)

Fly management is an identification problem first: the control changes completely depending on whether you have a filth fly, a small fly breeding in a drain, or an overwintering cluster fly.

• Small fruit / vinegar / pomace flies — Drosophila spp.
• House fly (Musca domestica) and lesser house fly (Fannia canicularis)
• Moth / drain / filter / sewer flies — family Psychodidae
• Phorid / humpbacked / scuttle flies — family Phoridae
• Fungus gnats — families Mycetophilidae and Sciaridae
• Blow flies — family Calliphoridae
• Cluster flies — Pollenia rudis
• Flesh flies — family Sarcophagidae
• Stable fly — Stomoxys calcitrans
• Horse and deer flies — family Tabanidae
• Small dung flies — family Sphaeroceridae
• Crane flies — family Tipulidae
• Soldier flies — family Stratiomyidae

Section 3 — Ants (Family Formicidae)

Ants are the number-one structural pest by call volume, and the exam expects you to distinguish species because their nesting, foraging, and bait strategies differ sharply.

• Carpenter ants — Camponotus spp.
• Odorous house ant — Tapinoma sessile
• Red imported fire ant — Solenopsis invicta
• Pavement ant — Tetramorium caespitum
• Pharaoh ant — Monomorium pharaonis
• Argentine ant — Linepithema humile
• Little black ant — Monomorium minimum
• Acrobat ants — Crematogaster spp.
• Crazy ant — Paratrechina longicornis
• Ghost ant — Tapinoma melanocephalum
• White-footed ant — Technomyrmex albipes
• Big-headed ants — Pheidole spp.
• Field ants — Formica spp.
• Harvester ants — Pogonomyrmex spp.

Section 4 — Cockroaches (Order Blattodea)

A small section, but a critical one — the German cockroach alone drives a huge share of urban pest work, and the exam expects you to know the peridomestic species too.

• German cockroach — Blattella germanica
• Asian cockroach — Blattella asahinai
• American cockroach — Periplaneta americana
• Brownbanded cockroach — Supella longipalpa
• Smokybrown cockroach — Periplaneta fuliginosa
• Oriental cockroach — Blatta orientalis
• Australian cockroach — Periplaneta australasiae
• Woods cockroaches — Parcoblatta spp.
• Surinam cockroach — Pycnoscelus surinamensis

Section 5 — Stored Product & Fabric Pests

The second-largest section. These are the pests of pantries, warehouses, museums, and closets — beetles and moths that feed on grain, dried goods, and natural fibers. Identification down to genus is often required.

• Indian meal moth — Plodia interpunctella
• Cigarette beetle (Lasioderma serricorne) & drugstore beetle (Stegobium paniceum)
• Carpet / domestic beetles — Anthrenus and Attagenus spp.
• Clothes moths — family Tineidae
• Flour beetles — Tribolium spp.
• Sawtoothed & merchant grain beetles — Oryzaephilus spp.
• Warehouse & cabinet beetles — Trogoderma spp.
• Psocids (booklice) — order Psocoptera
• Rice weevil (Sitophilus oryzae) & maize weevil (Sitophilus zeamais)
• Hide & larder beetles — Dermestes spp.
• Angoumois grain moth — Sitotroga cerealella
• Mediterranean flour moth — Ephestia kuehniella
• Foreign grain beetle — Ahasverus advena
• Plaster beetles — family Lathridiidae
• Spider beetles — family Ptinidae
• Mealworm beetles — Tenebrio spp.
• Dust mites — Dermatophagoides farinae
• Bean weevil — Acanthoscelides obtectus
• Flat grain beetle — Cryptolestes pusillus
• Cowpea weevil — Callosobruchus maculatus
• Red-legged ham beetle — Necrobia rufipes
• Cadelle — Tenebroides mauritanicus

Section 6 — Wood-Destroying Insects

The highest-liability section: termites and wood-boring beetles that damage structures. Distinguishing an active from an inactive infestation, and one species from another, changes both the treatment and the report.

• Subterranean termites — Reticulitermes and Coptotermes spp.
• Carpenter ants — Camponotus spp.
• Formosan termite — Coptotermes formosanus
• Carpenter bee — family Xylocopidae
• Drywood termites — Kalotermes approximatus, Incisitermes and Cryptotermes spp.
• Lyctine powderpost beetles — family Bostrichidae, subfamily Lyctinae
• Old house borer — Hylotrupes bajulus
• Anobiine beetles — family Ptinidae, subfamily Anobiinae
• Bostrichid (false powderpost) beetles — family Bostrichidae
• Long-horned beetles — family Cerambycidae
• Dampwood termites — Zootermopsis and Neotermes spp.
• Metallic wood-boring beetles — family Buprestidae

Section 7 — Occasional Invaders & General Household Pests

The “everything else” section: arthropods that wander indoors from the landscape. Control is usually about exclusion and conducive-condition correction, not chemistry.

• Silverfish — order Zygentoma (Thysanura)
• Springtails — order Collembola
• Earwigs — order Dermaptera
• Brown marmorated stink bug — Halyomorpha halys
• Millipedes — class Diplopoda
• Centipedes — class Chilopoda
• Boxelder bug — Boisea trivittata
• Sowbugs & pillbugs — order Isopoda
• House cricket — Acheta domesticus
• Cellar spiders — family Pholcidae
• Multicolored Asian lady beetle — Harmonia axyridis
• Ground beetles — family Carabidae
• Field cricket — Gryllus spp.
• Clover mite — Bryobia praetiosa
• Firebrat — order Zygentoma (Thysanura)
• Comb-footed (cobweb) spiders — family Theridiidae
• Camel (cave) cricket — Ceuthophilus spp.
• Thrips — order Thysanoptera
• Elm leaf beetle — Xanthogaleruca luteola
• Aquatic insect adults — orders Trichoptera, Ephemeroptera, Plecoptera

Section 8 — Common Commensal (Vertebrate) Pests

The ACE is not only about insects. The exam expects you to know the commensal rodents, birds, and bats that share human structures — their biology, signs, and management.

• House mouse — Mus musculus
• Norway rat — Rattus norvegicus
• Roof rat — Rattus rattus
• Pigeon / rock dove — Columba livia
• Deer mouse — Peromyscus spp.
• English (house) sparrow — Passer domesticus
• European starling — Sturnus vulgaris
• Commensal bats — order Chiroptera

How to actually pass the ACE exam

ESA is blunt that this isn’t a cram exam — plan on at least 40 hours of focused study, more if your day-to-day work is narrow. A practical study plan:

1. Study to the weighting. Domains 1 and 3 are 73% of the exam. Spend most of your time on pest identification and biology and on control-method selection, labels, formulations, modes of action, and resistance.
2. Master the pest list systematically. Work section by section, top to bottom (remember they’re ordered by likelihood). For each pest, learn the common name, scientific name, key ID features, life cycle, damage/medical importance, and control approach. Make flashcards for the scientific names.
3. Learn the regulatory and safety backbone. FIFRA, EPA’s role, restricted-use pesticides, state-vs-federal authority, label reading, and the banned/historical chemistries (DDT, chlordane, lindane; carbamates; organophosphates).
4. Know your IPM decision-making. Thresholds, monitoring tools (light traps, pheromone traps, glueboards), and the least-hazardous-effective-method principle.
5. Take the free ESA sample exam to gauge readiness before you schedule.

Recommended study resources

ESA’s own and classic references:

• ESA ACE Exam Prep Course and IPM for the Urban Professional: A Study Guide for the ACE (ESA).
• Truman’s Scientific Guide to Pest Management Operations (Bennett, Owens & Corrigan).
• Mallis Handbook of Pest Control (Mallis).
• NPMA Field Guide to Structural Pests (and the NPMA Field Guide App).
• The Hedges/Lacey field guides for ants, flies, and beetles; Koehler & Pereira, General Household Pest Control (UF/IFAS); Ware, The Pesticide Book; and the “Ace the ACE” podcast.

An ACE’s perspective: why this credential is more than a test

Passing the exam is the beginning, not the end. The reason the ACE matters is that it certifies a way of thinking — identify first, understand the biology, then choose the least-hazardous method that actually resolves the problem. That framework is what lets a professional solve the cases that stump everyone else:

• The recurring German cockroach problem that no spray fixes — because the answer is harborage-level treatment and building-aware thinking, not more chemical.
• The “bites with no bed bugs” case that three companies dismissed — because the real cause was bird mites from a nest, or a medical issue entirely, and only an entomologist could rule the insect in or out with evidence and feeding biology.
• The powderpost-beetle holes in an antique — because knowing active from inactive damage saves a client thousands.

New York Exterminating is led by Jorge Bedoya, an Associate Certified Entomologist (ACE) — a bilingual, conference-speaking entomologist who built his expertise the way the ACE was designed to recognize: through years in the field, continuous study, and a scientist’s discipline about evidence. If you’re a professional considering the credential, know this: it will change how you see every job, and it will earn you the trust of the clients who need real answers.

Frequently asked questions

Do you need a degree to become an ACE?

No. The ACE was designed for practicing professionals whose training came through experience and self-study. Without a degree you need 5 years of verifiable pest management experience, a current applicator’s license, and a passing exam. A related degree reduces the experience requirement to 3 years (bachelor’s), 2 (master’s), or 1 (PhD).

How much experience do you need for the ACE?

Five years of verifiable U.S. pest management experience without a degree; 3, 2, or 1 year with a bachelor’s, master’s, or PhD respectively.

How hard is the ACE exam?

It is a serious professional exam: 150 closed-book questions in 3 hours, 75% to pass, built on four domains and about 130 pests. ESA recommends at least 40 hours of study. Weight your prep toward Inspection & Identification (45%) and Control Methods (28%).

How many pests are on the ACE exam?

About 130, across 8 sections: Biting & Stinging, Flies, Ants, Cockroaches, Stored Product & Fabric, Wood-Destroying, Occasional Invaders, and Commensal vertebrates. The list is the same worldwide.

How much does the ACE cost?

$395 (non-member) or $355 (member) to apply, including the first year and the exam. Renewal is every 3 years for $375 / $295 with 18 CEUs.

How long is the ACE valid and how do you renew it?

Every 3 years, no retesting — document 18 CEUs, submit a current license, sign the Code of Ethics, and pay the fee. Inactive and emeritus statuses exist.

Is the ACE credential worth it?

For a career professional, yes. It is a recognized, third-party proof of entomological competence that differentiates you, builds trust, and is often rewarded by employers — and it’s the credential behind the professionals trusted with the toughest cases.

The Four Knowledge Domains In Depth

The ACE exam is organized around four knowledge domains that together describe the entire integrated pest management (IPM) cycle. Each is weighted differently, and each deserves real study. We’ve written a dedicated, in-depth guide for every one:

• Inspection & Identification (about 45% of the exam) — the largest domain: the professional inspection sequence, the inspector’s toolkit, reading evidence (droppings, frass, egg cases, mud tubes), conducive conditions, and identifying pests by taxonomy, morphology, and metamorphosis.
• Monitoring (about 12% of the exam) — the data engine of IPM: sticky monitors, insect light traps, pheromone lures, rodent multi-catch devices, bed-bug interceptors, placement principles, thresholds, and reading trends.
• Selection & Implementation of Control Methods (about 28% of the exam) — the four control categories (cultural, biological, mechanical, chemical), the least-hazardous-effective principle, formulations, modes of action, resistance management, and FIFRA labels.
• Evaluation (about 15% of the exam) — closing the loop: verifying control with pre- and post-treatment data, diagnosing failure and resistance, documentation, and third-party audits.

Together these four articles form a complete study companion to this guide. And when you’re ready to test yourself, try our free 600-question ACE practice exam — original questions weighted across all four domains, with instant scoring and explanations.