If you keep finding roaches in your bathroom, you’re not alone — and no, it doesn’t automatically mean your home is dirty. Bathrooms are one of the most common places homeowners see cockroach activity, even when the rest of the house seems pest-free. In Arizona, especially in cities like Queen Creek, Phoenix, and Tucson, and across Southern Arizona, warm temperatures, plumbing access, and the constant search for moisture make bathrooms a common trouble spot.

Cockroaches are survival experts. When they enter a home, they look for three things: water, shelter, and warmth. Bathrooms check all three boxes.

cockroach infestation inside az bathroom


Quick Answer: Why Do I Have Roaches in My Bathroom?

Roaches are attracted to bathrooms because they provide moisture from sinks, showers, toilets, and drains, as well as dark hiding places behind walls, cabinets, and baseboards. Even minor plumbing leaks or condensation can be enough to attract them.

Common Reasons You’re Seeing Roaches in the Bathroom

1. Moisture and Water Sources

In the desert climate of Southern Arizona, indoor water sources like bathrooms are among the most reliable places for cockroaches to survive year-round. Bathrooms provide:

  • Leaky faucets or pipes
  • Condensation on plumbing
  • Standing water in tubs or sinks
  • Moisture inside drains

Even a slow drip or damp cabinet can draw roaches inside.

2. Access Through Drains and Plumbing Lines

Cockroaches often travel through:

  • Sink and shower drains
  • Pipe openings under cabinets
  • Gaps around plumbing penetrations

If you’re seeing roaches only in the bathroom, they may be entering directly through the plumbing system rather than spreading throughout the house.

3. Hidden Food Sources

Bathrooms still provide food for roaches, including:

  • Soap residue
  • Hair and skin cells
  • Toothpaste splatter
  • Trash or used paper products

These small food sources are more than enough to sustain roaches.

4. Warm, Dark Hiding Spots

Bathrooms offer excellent hiding places, such as:

  • Behind toilets
  • Under sinks
  • Inside vanity cabinets
  • Along baseboards and tile cracks
  • Behind wall voids

Roaches prefer to stay hidden during the day, which is why many homeowners spot them at night.

Where Do Roaches Hide in Bathrooms?

If you’re seeing a cockroach in the bathroom, it’s likely hiding nearby. Common hiding spots include:

  • Under sink cabinets
  • Inside wall voids behind plumbing
  • Around floor drains
  • Behind baseboards and loose tile
  • Under bath mats and rugs

Seeing one roach often means others are nearby, even if you don’t see them right away.

What If You’re Seeing Baby Cockroaches in the Bathroom?

Seeing baby cockroaches (nymphs) in your bathroom is often a sign that roaches aren’t just passing through — they’re nesting nearby. Baby roaches don’t travel far from where they hatch so the source may be in wall voids, behind cabinets, or around plumbing lines.

Bathrooms provide the moisture and shelter young roaches need to survive, especially in warm regions like Phoenix and Tucson. If baby roaches keep appearing, it usually indicates an active infestation, not an isolated issue.

What Attracts Roaches to Bathrooms Specifically?

Bathrooms attract roaches more than other rooms because they combine:

  • Reliable water access
  • Consistent warmth
  • Low foot traffic at night
  • Hidden entry points

In desert environments like Arizona, bathrooms can become a primary survival zone for roaches inside a home.

How to Get Rid of Roaches in Your Bathroom

Step 1: Eliminate Moisture

  • Fix dripping faucets and leaks immediately
  • Dry sinks and tubs before bed
  • Use bathroom exhaust fans to reduce humidity
  • Avoid leaving wet towels or bath mats on the floor

Step 2: Clean Drains and Hidden Areas

  • Flush drains regularly
  • Use enzyme-based drain cleaners
  • Clean under sinks and behind toilets
  • Empty bathroom trash frequently

Step 3: Seal Entry Points

  • Seal gaps around plumbing lines
  • Repair cracked grout and caulk
  • Seal baseboard gaps
  • Close wall voids where pipes enter

Step 4: Be Cautious With DIY Roach Products

Many homeowners try sprays, foggers, or over-the-counter baits, but these products often provide limited or temporary results in bathrooms.

Common issues with DIY treatments include:

  • Killing only the roaches you see
  • Causing roaches to scatter deeper into walls or plumbing
  • Failing to reach hidden nesting areas
  • Not addressing moisture or entry points

Sticky monitors can help confirm activity, but most store-bought products won’t solve a bathroom roach problem on their own — especially if roaches are entering through drains or wall voids.

How Ongoing Home Pest Control Helps Prevent Bathroom Roaches

Because bathroom roach problems are often tied to moisture, plumbing access, and hidden harborages, one-time treatments don’t always provide lasting results. This is especially true in Phoenix, Tucson, and Southern Arizona, where cockroaches can remain active much of the year.

Ongoing home pest control helps prevent cockroaches by:

  • Monitoring and treating hidden activity before it spreads
  • Targeting plumbing lines, wall voids, and common entry points
  • Reducing recurring roach pressure from outside the home
  • Helping control other pests that thrive in similar conditions

Regular service allows technicians to adjust treatments seasonally and address new issues early — before roaches become a recurring bathroom problem.

When to Call Northwest Exterminating

If roaches keep appearing in your bathroom despite cleaning and sealing efforts, it’s often a sign of a hidden source, such as wall voids, plumbing lines, or moisture issues that aren’t visible on the surface.

Northwest Exterminating provides ongoing home pest control services throughout Phoenix, Tucson, and Southern Arizona, designed to help prevent cockroaches and other common household pests before they become persistent problems.

Our technicians don’t rely solely on surface sprays. Instead, we focus on:

  • Locating where roaches are entering through plumbing and wall voids
  • Targeting harborages behind walls, under cabinets, and around drains
  • Addressing moisture-related attractants that keep roaches coming back
  • Using professional-grade treatments designed for long-term control

Because bathroom roach problems are often linked to the home's structure, professional treatment helps eliminate the issue at the source—not just the symptoms.

Roaches in the Bathroom Are Common, but They Don’t Have to Be Your Problem

Finding roaches in your bathroom is frustrating, but it’s also one of the most common issues Northwest Exterminating helps homeowners resolve. By reducing moisture, sealing access points, and addressing hidden roach activity inside walls and plumbing areas, long-term control is possible.

If bathroom roaches persist, a professional inspection from Northwest Exterminating can identify the cause and provide a targeted solution designed to keep them from returning.

If roaches keep showing up in your bathroom (or other areas of your home), it may be time to have a professional take a look. Northwest Exterminating can help identify the source and stop the problem before it returns!

Originally published on January 18, 2023; Updated for accuracy and relevancy in 2026.