Short answer
To compare low and high sanitization and fogging bids, put both on the same scope: areas treated, pre-cleaning of surfaces, the exact product and whether its label allows the method, contact time, re-entry timing, and any verification such as ATP testing. A low bid can be fine if it covers those steps. A high bid should explain what the added cost buys and why your space needs it.
Why quotes vary, and what each bid should spell out
Sanitization and fogging services range from a quick mist of a room to a multi-step process that includes cleaning, targeted disinfection, and testing. Two companies can quote the same office and come back with numbers that look unrelated. Usually they are describing different work.
One company may price only the fogging pass, assuming surfaces are already clean. Another may include wiping high-touch surfaces first, choosing a product labeled for the specific pathogen, holding contact time, and running verification tests afterward. The second job takes longer, uses more product, and costs more.
Your job is not to find the lowest or highest bid. It is to make them comparable, so you can see what each company is actually offering and decide which one fits the need.
How the bid was prepared tells you something too. A price given over the phone from square footage alone is an estimate based on assumptions. A bid prepared after a walk-through, with notes on room types, surfaces, and ventilation, is more likely to reflect the real work and less likely to change later.
Ask every company to describe its work in writing. A clear scope is the best tool you have for comparing prices fairly.
Once you have the scopes, mark each line as included, excluded, or unclear. Follow up on anything unclear before comparing prices.
- Areas to be treated, with square footage or room list.
- Whether surfaces are cleaned before disinfection, and which ones.
- The exact product name and EPA registration number.
- Whether the product label allows fogging or electrostatic application.
- The contact time the label requires and how it will be maintained.
- How long the space must stay empty afterward.
- Any verification, such as ATP testing or visual inspection.
- Frequency and pricing for recurring service.
Why does pre-cleaning change the value of a bid?
A disinfectant does its job best on a surface that has already been cleaned. Dirt, grease, and body oils can shield microorganisms and weaken the active ingredient. A fog applied over grimy desks and door handles may leave the surfaces wet without doing much good.
Physically touching the surface, with a cloth and detergent, is what removes that barrier. No mist does it for you.
A bid that includes cleaning high-touch surfaces first will cost more than one that only fogs. In many settings, it is the better value.
When you compare bids, look at which surfaces each company plans to clean by hand. Door handles, light switches, faucet handles, shared keyboards, railings, and tabletops carry the most traffic. A bid that names them specifically is easier to hold to account than one that promises a general wipe-down.
Low bid vs high bid: when each makes sense
A lower price is not a problem by itself. A small space, a company with nearby crews, or a simpler scope can all produce a legitimately lower bid. If your custodial team already cleans the space thoroughly each night, a targeted disinfection pass may be all you need.
The test is whether the low bid includes the essentials: a product whose label covers the target organism and allows the application method, enough product to keep surfaces wet for the contact time, and clear re-entry instructions.
Low bids become a problem when the savings come from shortcuts: skipping cleaning, using a product not labeled for fogging, rushing through without maintaining contact time, or using a fragranced product that smells clean but is not registered as a disinfectant. These shortcuts can leave you paying for a service that looks good but delivers little.
Ask the low bidder how much product it expects to use and how it knows surfaces will stay wet long enough. A company that can answer in terms of the label and the room, rather than the look of the fog, is more likely to deliver a real result.
A higher bid should point to specific added value. Examples include pre-cleaning of high-touch surfaces, a product chosen for a specific pathogen after an outbreak, verification testing, or detailed documentation for regulated settings like healthcare or food service.
Some methods take longer by design. Room-sealing vapor systems, for example, can be justified in certain settings but carry real costs in time and equipment.
Treat loosely described add-ons with some skepticism. Ozone treatments, "antimicrobial coatings," or "hospital-grade" packages without details deserve a direct question: what specific problem does this solve in my space, and what evidence supports it?
Verification and recurring service
Some bids include ATP testing, which measures organic residue on surfaces and gives a quick indication of cleanliness. Others include no testing. Testing adds cost but gives you data rather than impressions.
ATP results are not a direct measure of germs, and pass/fail benchmarks vary. Different devices and settings use different thresholds, so a number from one company's meter cannot be compared directly with another's.
If a bid includes testing, ask which surfaces will be tested, what device is used, what result the company considers passing, and what happens if a surface fails. Testing is most useful when it leads to action.
Visual inspection still has a place. A walk-through after treatment, checking that surfaces were reached and that no residue or puddles were left on electronics or food-contact areas, costs little and catches obvious problems. Ask whether that is part of each bid.
Many fogging contracts are recurring: weekly, monthly, or seasonal. Compare the per-visit scope, not just the monthly price. A lower monthly fee that covers fewer areas or skips pre-cleaning may not be a better deal.
Ask how the provider decides the right frequency. A thoughtful answer ties frequency to how the space is used, occupancy, outbreak risk, and what your custodial team already does. A provider that recommends frequent fogging for every client regardless of need may be selling more service than you require.
Check contract terms too. Look for how either side can end the agreement, whether prices can change mid-term, and what happens if a visit is missed.
It is also worth asking whether recurring visits will be adjusted over time. If illness reports drop or your custodial program improves, a good provider may suggest reducing frequency or shifting to targeted treatment of high-risk areas. That willingness to scale back is a sign the company is focused on outcomes rather than volume.
Three bids for a small daycare
For illustration, take a daycare director who wants disinfection help after a stomach bug moves through two classrooms and asks three companies for bids to treat the classrooms, restrooms, and kitchen.
Bid A is the lowest and covers a full-building fog with a product the company describes as "hospital grade." When she asks, the company cannot say whether the label lists norovirus or allows fogging. Bid B is in the middle and includes cleaning of high-touch surfaces, toys, and tables, followed by electrostatic application of a product whose label lists norovirus and allows that method, with the rooms closed for the contact time and a food-contact rinse in the kitchen as the label requires. Bid C is the highest and adds ozone treatment and a monthly contract.
Lining up the scopes, the director sees that Bid A cannot confirm it uses the right product. Bid C's ozone treatment raises safety questions for a space with children and does not address the need. Bid B covers the actual problem. She chooses it for a one-time service and asks for a written summary to share with parents.
Last checks before signing
A handful of last questions, answered in writing, can settle the decision. They help confirm you are comparing like with like and that the company will stand behind the work.
If your state requires licensing for disinfectant applicators, or if you operate a regulated facility such as a clinic or food business, confirm those requirements with your state pesticide regulatory agency or licensing agency before you sign. A provider that answers these questions clearly is usually the one that will do careful work.
- Can I see the label for the product you will use?
- Does the label allow the application method you plan to use?
- What will you clean before disinfecting?
- How long will the space stay closed, and why?
- If I showed you a competitor's scope, what would you charge for exactly that work?
