Quick answer
In NYC, cockroaches and bed bugs are year-round indoors, ants and stinging insects peak in late spring through summer, mosquitoes peak June–September, and rodents surge indoors in fall as temperatures drop. Use the month-by-month table below to prevent each pest before its peak.
When does each NYC pest peak?
Cockroaches and bed bugs are year-round indoor pests in NYC; ants and stinging insects peak from late spring through summer; mosquitoes peak June through September; and rodents surge indoors in the fall. The calendar below shows when each common New York pest is most active — and the best time to act is 30–60 days before a peak.
| Month | Peaking pests | Prevention focus |
|---|---|---|
| January–February | Rodents (indoors), cockroaches | Seal entry points; winter rodent exclusion |
| March | Ants (early), rodents | Spring ant baiting before trails establish |
| April | Ants, termites (swarm season), stinging insects (early) | Termite inspection; ant prevention |
| May | Ants, stinging insects, mosquitoes (early) | Yard/mosquito source reduction |
| June | Mosquitoes, ticks, stinging insects, flies | Mosquito & tick treatment begins |
| July | Mosquitoes, flies, stinging insects, cockroaches | Peak outdoor + commercial fly pressure |
| August | Mosquitoes, stinging insects (aggressive), roaches | Wasp/hornet nest removal |
| September | Rodents (moving indoors), stinging insects | Begin fall rodent-proofing |
| October | Rodents, occasional invaders (spiders, etc.) | Rodent exclusion is most important now |
| November | Rodents (indoors) | Seal gaps before deep cold |
| December | Rodents, cockroaches (indoors) | Holiday food-storage hygiene |
Year-round in NYC
Some pests don’t follow the seasons because they live indoors in heated buildings:
- Cockroaches (German + water bugs) — year-round in kitchens, bathrooms and drains.
- Bed bugs — year-round; spread spikes around moving periods and travel.
- Mice & rats — active all year; activity indoors peaks in fall.
How to use this calendar
Treat before the peak. Spring ant baiting before trails establish, mosquito treatment starting in June, and rodent-proofing in early fall are far more effective (and cheaper) than reacting after an infestation. A recurring maintenance plan handles this automatically, adjusting by season.