FAQ

Pest control questions, answered

Identify the pest first; each profile below covers identification and the control steps extension specialists recommend.[17]

The short answer

  • If you use a pesticide, read the label first, choose the lowest-toxicity product that will work, and use only the amount the label calls for.[17]
  • Keep children, pets and sensitive people out of the treatment area during and after application.[17]
  • Seal every gap and opening larger than 1/4 inch; house mice can squeeze under gaps 1/4 inch tall and young rats under a door with a 1/2-inch gap.[11][18]

Hiring a company

  • Get written estimates from more than one licensed company.[12][19][20]
  • Compare the first-year price and any annual renewal fee, and ask what the guarantee covers.[21][19]
  • Be wary of a price quoted per gallon of pesticide, a 'secret formula', or pressure to sign immediately.[1]

Common questions

How do I check that a pest control company is licensed?
Ask the company for its license number and the name of the technician who will do the work. A company must have at least one certified, licensed commercial applicator in the proper service category.[1]
How long after spraying is it safe to go back in?
For most indoor and lawn treatments, the label says to stay off treated surfaces until the spray has dried.[2][3]
Should kids, pregnant women and pets stay out longer?
Babies, pregnant women and pets should stay out until the area is both dry and well ventilated.[4][5]
Do ultrasonic pest repellers work?
Ultrasonic and electromagnetic repellers: the FTC has said ultrasound does not control insects and that any rodent reaction is temporary.[6]
Why don't sprays get rid of cockroaches or ants?
For cockroaches and ants, baits beat sprays: sprays alone won't eliminate German cockroaches, and spraying while baiting works against the bait.[7][8]
What actually works against mosquitoes?
For mosquitoes, use an EPA-registered repellent and remove standing water; zappers, wristbands, mosquito plants and vitamin B1 don't work.[9][10]
What size gap can a mouse get through?
House mice can squeeze under gaps 1/4 inch tall and through openings 3/8 inch wide; seal anything larger than 1/4 inch.[11]
Can I seal mouse holes with expanding foam?
No. UC IPM lists insulating foam, plastic, rubber, vinyl and wood among the materials mice chew through; use metal or concrete.[11]
How much does pest control cost?
Prices depend on the company, the home and the infestation, and we haven't found an authoritative current source for them. Written estimates from several licensed companies are the reliable way to know.[12]
How soon should I remove a tick?
As soon as you find it; Lyme bacteria usually pass only after the tick has fed for about 36 hours.[13][14]
Can a doctor tell what bit me?
Usually not reliably; reactions vary, and conditions such as staph infections are often mistaken for spider bites.[15][16]

Sources

  1. U.S. Environmental Protection Agency, “Tips for Selecting a Pest Control Service.” www.epa.gov/safepestcontrol/tips-selecting-pest-control-service (accessed 2026-10-06)
  2. Health Canada, “For everyone's safety, be patient after pesticides have been applied.” www.canada.ca/en/health-canada/services/publications/product-safety/everyone-safety-patient-after-pesticides-applied.html (accessed 2026-10-06). Canadian regulator; quoted for its examples of label re-entry wording
  3. U.S. EPA Pesticide Product Label System, “Bifenthrin TC (Bifen I/T) label, EPA Reg. No. 53883-118 (EPA-stamped, September 1, 2026).” www3.epa.gov/pesticides/chem_search/ppls/053883-00118-20260901.pdf (accessed 2026-10-06)
  4. National Pesticide Information Center, “PestiBytes Episode 8: With a Baby on the Way... Is It Okay to Spray?.” npic.orst.edu/pestibytes/ep8.html (accessed 2026-10-06)
  5. National Pesticide Information Center, “Pesticide Use Around Pets.” npic.orst.edu/health/pets.html (accessed 2026-10-06)
  6. Iowa State University Extension, “Ultrasonic Pest Control - Buyer Beware (reprints FTC release of May 3, 2001).” yardandgarden.extension.iastate.edu/article/2001/8-24-2001/ultrasonic.html (accessed 2026-10-06)
  7. University of California Statewide IPM Program, “Pest Notes: Cockroaches, Publication 7467 (revised December 2019).” ipm.ucanr.edu/legacy_assets/PDF/PESTNOTES/pncockroaches.pdf (accessed 2026-10-06)
  8. University of California Statewide IPM Program, “Pest Notes: Ants, Publication 7411 (October 2012).” ipm.ucanr.edu/legacy_assets/PDF/PESTNOTES/pnants.pdf (accessed 2026-10-06)
  9. University of California Statewide IPM Program, “Pest Notes: Mosquitoes, Publication 7451 (April 2020).” ipm.ucanr.edu/legacy_assets/PDF/PESTNOTES/pnmosquitoes.pdf (accessed 2026-10-06)
  10. U.S. Centers for Disease Control and Prevention, “Preventing Mosquito Bites.” www.cdc.gov/mosquitoes/prevention/index.html (accessed 2026-10-06)
  11. University of California Statewide IPM Program, “Pest Notes: House Mouse, Publication 7483 (revised July 2025).” ipm.ucanr.edu/legacy_assets/PDF/PESTNOTES/pnhousemouse.pdf (accessed 2026-10-06)
  12. University of Kentucky Entomology, “ENTFACT-604: Termite Control: Answers for Homeowners (revised March 2026).” entomology.mgcafe.uky.edu/ef604 (accessed 2026-10-06)
  13. University of Kentucky Entomology, “ENTFACT-618: Ticks and Disease in Kentucky.” entomology.mgcafe.uky.edu/ef618 (accessed 2026-10-06)
  14. Centers for Disease Control and Prevention, “What to Do After a Tick Bite.” www.cdc.gov/ticks/after-a-tick-bite/index.html (accessed 2026-10-06)
  15. University of California Statewide IPM Program, “Pest Notes: Bed Bugs, Publication 7454 (May 2013).” ipm.ucanr.edu/legacy_assets/PDF/PESTNOTES/pnbedbugs.pdf (accessed 2026-10-06)
  16. University of Kentucky Entomology, “ENTFACT-631: Brown Recluse Spider.” entomology.mgcafe.uky.edu/ef631 (accessed 2026-10-06)
  17. National Pesticide Information Center, “Minimizing Pesticide Exposures.” npic.orst.edu/health/minexp.html (accessed 2026-10-06)
  18. University of California Statewide IPM Program, “Pest Notes: Rats, Publication 74106 (revised June 2024).” ipm.ucanr.edu/legacy_assets/PDF/PESTNOTES/pnrats.pdf (accessed 2026-10-06)
  19. National Pesticide Information Center, “Selecting a Pest Control Company.” www.npic.orst.edu/pest/selectpco.html (accessed 2026-10-06)
  20. University of Minnesota Extension, “Hiring a pest control professional.” extension.umn.edu/home-maintenance-and-safety/hiring-pest-control-professional (accessed 2026-10-06)
  21. University of Kentucky Entomology, “ENTFACT-639: Termite Baits: A Guide for Homeowners.” entomology.mgcafe.uky.edu/ef639 (accessed 2026-10-06)

Updated 2026-10-06. Built from sourced records. Spot an error? Tell us.