Who Actually Does the Work: A Concentration Census of California Pest Control Licences
Key result: 4,737 licences reported structural pest control work in California in 2022. The most active 10 percent made 79.2 percent of the 18.3 million applications; the least active half made 0.9 percent. The 47 licences doing the most applications and the 47 applying the most pounds are almost entirely different businesses.
What a licence number represents, before any of the numbers
California requires structural pest control businesses to report their pesticide use every month, and every report carries a licence number. That field is what makes this analysis possible, and its limits set the limits of everything below.
The field identifies the entity that filed the report. We did not establish whether one licence number corresponds to one business, one branch of a larger business, or one individual, because the published reference files do not say. For that reason this report uses the word licence throughout, never the word company, and names no business. The measures below describe how reported work is distributed across licence numbers, which readers should treat as a close proxy for how work is distributed across operators.
Two further boundaries. This covers site code 10, structural pest control, and excludes landscape, public health, vertebrate and agricultural work. And it is California only.
How many licences, exactly. The licence field is not entered consistently. The same number can appear with and without a space or leading zero, such as “PR 0829” and “PR829”, and some reports give a bare number with no licence-type prefix. Counting raw values gives 4,737 licences in 2022; standardising spaces and leading zeros gives 4,483. Because bare numbers can belong to either a principal or a branch registration, we do not merge them further. The concentration measures in this report move by less than half a percentage point between the two counts: on the standardised count, the top 10 percent made 79.0 percent of applications in 2022 and the Gini coefficient was 0.866. The same inconsistency makes year-to-year tracking of individual licences unreliable, which is why this report does not measure entry, exit or turnover.
The concentration result
Each monthly report states how many applications of one product the business made that month. Summing that application count by licence gives each licence’s reported workload for the year.
| Most active share of licences | Licences | Share of applications, 2022 | Share of applications, 2023 |
|---|---|---|---|
| Top 1% | 47 | 34.4% | 36.6% |
| Top 5% | 237 | 66.0% | 66.8% |
| Top 10% | 474 | 79.2% | 79.9% |
| Top 25% | 1,184 | 93.3% | 93.6% |
| Least active 50% | 2,368 | 0.9% | 0.8% |
Source: California Department of Pesticide Regulation, Pesticide Use Reports 2022 and 2023, site code 10, applications summed by licence number. Licence counts are for 2022. Author calculation.
Reading it. The most active tenth of licences reported four in every five structural applications in California. The most active 1 percent, 47 licences, reported a third. The median licence reported 340 applications in the year, in both years. The Gini coefficient of applications per licence is 0.867 in 2022 and 0.872 in 2023, where 0 is perfectly even and 1 is one licence doing everything.
What that is and is not. This is a measure of reported application events, not revenue, market share or profit. A licence running many recurring service routes will rank above a licence doing fewer large jobs. 562 licences, 11.9 percent, filed reports in 2022 without stating any application count; they are included with zero applications, which raises the measured concentration somewhat.
Does the unit of measurement change the answer?
It changes the number a great deal and the direction not at all. The same 4,737 licences, measured four ways:
| Unit of activity, 2022 | Total units | Top 1% | Top 10% | Top 25% | Median per licence | Gini |
|---|---|---|---|---|---|---|
| Applications, as reported | 18,268,755 | 34.4% | 79.2% | 93.3% | 340 | 0.867 |
| Monthly reports | 498,455 | 15.2% | 51.2% | 74.1% | 45 | 0.654 |
| Active-ingredient rows | 657,555 | 15.9% | 53.5% | 76.6% | 52 | 0.679 |
| Pounds of active ingredient | 3,897,322 | 62.3% | 96.1% | 99.0% | 10.9 | 0.961 |
Source: as above. Author calculation.
What it means. Counting reports or rows treats a report covering three applications the same as one covering three thousand, and puts the top decile at about half of all activity. Counting the applications those reports state puts it at four fifths. The large operators do not file many more reports than small ones; each of their reports covers far more work. The application count is the unit the department defines as the number of applications, so it is the headline measure here.
Limits. None of the units is a count of customer visits, which the dataset does not record. An application is what the business reports as one, so a bait-station check and a whole-house fumigation each count once.
The shape of the tail
| Applications reported in 2022 | Licences | Share of licences | Share of applications |
|---|---|---|---|
| None stated | 562 | 11.9% | 0.0% |
| 1 to 9 | 347 | 7.3% | 0.0% |
| 10 to 99 | 803 | 17.0% | 0.2% |
| 100 to 999 | 1,398 | 29.5% | 3.2% |
| 1,000 to 9,999 | 1,283 | 27.1% | 23.2% |
| 10,000 or more | 344 | 7.3% | 73.3% |
Source: as above. Author calculation.
What it means. 344 licences reported 10,000 or more applications each in 2022 and between them made almost three quarters of all structural applications in the state. 909 licences reported fewer than ten or none. The same pattern appears in 2023, when 349 licences above 10,000 made 74.7 percent.
What it does not mean. A licence reporting few structural applications is not necessarily a small business. It may do most of its work under another site code, or have entered structural work late in the year.
Two industries under one site code
The most striking result is what happens when the top licences by applications are set beside the top licences by pounds.
| Group, 2022 | Share of applications | Share of pounds |
|---|---|---|
| Top 1% by applications, 47 licences | 34.4% | 4.0% |
| Top 1% by pounds, 47 licences | 2.6% | 62.3% |
| Top 10% by applications | 79.2% | 12.0% |
| Top 10% by pounds | 52.3% | 96.1% |
| Licences in both top 1% groups | 1 of 47 in 2022, 3 of 46 in 2023 | |
Source: as above. Author calculation.
What it means. The 47 licences that apply the most weight and the 47 that make the most applications are, with one exception, different licences. The weight leaders apply 62 percent of all structural pounds while reporting under 3 percent of applications. The volume leaders report a third of all applications while applying 4 percent of the weight. Our analysis of what structural pest control applies found that sulfuryl fluoride is two thirds of all structural pounds at about 28 pounds per fumigation, against 0.07 pounds per application for everything else, so the weight leaders are, in effect, the fumigators. Whole-structure fumigation and recurring general pest service look like separate businesses that share a site code.
What limits it. We did not classify licences by the products they use, so “fumigators” is an inference from the pounds, not a label in the data. The broader top tenth by pounds still reports half of all applications, so many large operators do both kinds of work.
Geographic reach
1,934 licences, 40.8 percent of the total, reported work in more than one California county in 2022, and 41.6 percent did so in 2023. The median licence reported using nine distinct active ingredients over the year.
Limits. County count is a crude footprint measure. A licence operating either side of a county boundary looks identical to one covering two distant counties.
Does it hold in a second year?
| Measure | 2022 | 2023 |
|---|---|---|
| Distinct licences | 4,737 | 4,630 |
| Applications attributed to a licence | 18,268,755 | 18,812,725 |
| Share of applications, top 1% | 34.4% | 36.6% |
| Share of applications, top 10% | 79.2% | 79.9% |
| Share of applications, top 25% | 93.3% | 93.6% |
| Gini coefficient, applications | 0.867 | 0.872 |
| Median applications per licence | 340 | 340 |
| Licences stating no application count | 562 (11.9%) | 586 (12.7%) |
| Licences in more than one county | 40.8% | 41.6% |
Source: California Pesticide Use Reports 2022 and 2023, site code 10, calculated independently for each year. Author calculation.
What it means. The distribution barely moves between years, which suggests it is a property of the market rather than of one reporting year. Fewer than one row in a thousand lacks a licence number.
Limits. Two consecutive years is a replication, not a trend. We did not match licence numbers between years beyond the top 1 percent comparison.
Three measures we computed
1. Top decile workload share
Definition. The share of all reported applications made by the most active ten percent of licences.
Formula. Sort licences by applications, descending; sum the first 10 percent; divide by total applications.
Result. 79.2 percent in 2022 and 79.9 percent in 2023. On report or row counts, 51 to 54 percent.
Limitations. Licences that state no application count are included as zero. Says nothing about revenue.
2. Weight-work overlap
Definition. How many licences appear in both the top 1 percent by applications and the top 1 percent by pounds.
Formula. Size of the intersection of the two groups, divided by group size.
Result. 1 of 47 in 2022 and 3 of 46 in 2023.
Why it is useful. It shows directly that a pounds-based account of the industry describes different operators from a workload-based one. Limitations: the top 1 percent is a small group, and the overlap would rise in broader groups.
3. Reporting completeness
Definition. The share of structural rows carrying a usable licence number.
Result. 99.91 percent in 2022 (615 blank of 658,170 rows) and 99.93 percent in 2023 (481 of 672,218).
Limitations. Completeness is not correctness. We did not validate numbers against the state licence register.
Related research: federal FIFRA enforcement against pest control businesses.
Download the data
The tables in this report are published as CSV files under a Creative Commons Attribution 4.0 licence. You may republish, remix and build on them, including commercially, with attribution to The Pest Control Brief and a link to this page.
- Concentration under four units of activity, 2022 and 2023 (CSV, 8 rows)
- Cumulative share of applications and rows by licence decile, 2022 and 2023 (CSV, 20 rows)
- Licences by annual application count, 2022 and 2023 (CSV, 12 rows)
- Top licence groups by applications and by pounds, with their shares of each, 2022 and 2023 (CSV, 16 rows)
How to cite this report
The Pest Control Brief, “Who Actually Does the Work: A Concentration Census of California Pest Control Licences”, 2 October 2026. https://thepestcontrolbrief.com/california-applicator-concentration/
References
- California Department of Pesticide Regulation. Pesticide Use Report annual archives for 2022 and 2023. files.cdpr.ca.gov/pub/outgoing/pur_archives/. Accessed 2 October 2026. The licence number field is license_no and the application count field is applic_cnt in the county use files.
- California Department of Pesticide Regulation. PUR field definitions, readme_excel.xlsx, supplied inside the 2023 archive. Defines applic_cnt for non-agricultural monthly summary reports as the total number of applications of a single product.
- California Department of Pesticide Regulation. Structural Pesticide Use Report policy: total number of applications on monthly summary. cdpr.ca.gov structural PUR policy. Accessed 2 October 2026.
- California Structural Pest Control Board. pestboard.ca.gov. Noted as the licensing authority. We did not match reporting licence numbers against its register.
How the census was built
Source and scope. Every California Pesticide Use Report record for 2022 and 2023 with site code 10, Structural Pest Control, from the 58 county use files in each archive, grouped on the license_no field. No sampling.
Applications. The applic_cnt field, counted once per report (a report naming several active ingredients appears as several rows with the same count).
Other units. Distinct reports, active-ingredient rows, and pounds of active ingredient from the lbs_chm_used field.
Concentration statistics. Top-share figures sort licences by activity descending and sum the first N percent. The Gini coefficient uses the standard ordered formula on activity per licence, including licences with zero stated applications.
What we deliberately did not do. We did not link licence numbers to named businesses, did not validate them against the state register, and did not infer revenue, headcount or market share.
Corrections. Corrected 2 October 2026. The first version of this report, published the same day, counted rows in the use files as applications. California files structural use as monthly summary reports, and the number of applications each report covers is a separate field. Using that field, the top decile’s share is 79.2 percent, not 53.4 percent; the top 1 percent’s share is 34.4 percent, not 15.9; the least active half’s share is 0.9 percent, not 7.4; the Gini coefficient is 0.867, not 0.679; and the median licence reports 340 applications, not 52. The row-based figures remain in the unit-comparison table. The finding that pounds are far more concentrated than work is unchanged, and the weight-work overlap analysis was added.
Note added 3 October 2026. We found that licence numbers are recorded in inconsistent formats and added the section “How many licences, exactly”, with counts and concentration measures on a standardised basis. No headline figure changed by more than half a percentage point.
Last reviewed: 3 October 2026.
Source
Tier 1, primary government data. California Department of Pesticide Regulation, Pesticide Use Report archives 2022 and 2023. This is the only source used for any figure in this report.
Excluded. Trade-press and vendor estimates of operator counts and market share, because none publishes a method.
For analysts and reporters
Most quotable statistics
- The most active 10 percent of California structural pest control licences made 79.2 percent of the state’s 18.3 million structural applications in 2022.
- 344 licences each reported 10,000 or more applications and together made 73.3 percent of all applications.
- The least active half of licences made 0.9 percent of applications.
- Of the 47 licences applying the most pesticide by weight and the 47 making the most applications, only one is in both groups.
- The Gini coefficient of applications per licence was 0.867 in 2022 and 0.872 in 2023.
Figures to quote alongside them
A licence number identifies a reporting entity, not verifiably a single business. California only, structural work only. Applications are as reported on monthly summaries; a fumigation and a bait-station check each count as one. On report counts rather than applications, the top decile share is about half.
Fields in the published CSV files
Year; unit; total units; top 1, 5, 10 and 25 percent shares; least active half share; median per licence; Gini. Decile; cumulative share of applications and rows. Application band; licences; shares. Group; share of applications; share of pounds.
Press summary
Four fifths of California’s structural pest control applications are made by a tenth of the licences that report them, according to an analysis of state pesticide use reports by The Pest Control Brief. Of 4,737 licences reporting structural work in 2022, the most active 10 percent made 79.2 percent of 18.3 million applications, and 344 licences each reporting more than 10,000 applications made 73 percent between them. The least active half made under 1 percent. The analysis also finds two distinct industries under one site code: of the 47 licences applying the most pesticide by weight, dominated by whole-structure fumigation, and the 47 making the most applications, only one appears in both groups. The pattern repeats almost exactly in 2023.
Five headlines editors could use
- One tenth of California pest control licences make four fifths of the applications
- 344 operators do three quarters of California’s pest control treatments
- The fumigators and the route operators are almost never the same business
- Half of California’s pest control licences make under 1 percent of the treatments
- Why counting pounds tells you who fumigates, not who works
Questions about this census
How many pest control operators are there in California?
4,737 licence numbers reported structural work in 2022 and 4,630 in 2023. That is a count of reporting licences, not verifiably of businesses.
Do the biggest operators really do most of the work?
Yes, on reported applications. The most active tenth of licences made 79.2 percent of structural applications in 2022 and 79.9 percent in 2023.
How concentrated is California pest control?
The Gini coefficient of applications per licence was 0.867 in 2022, where 1 would mean a single licence doing everything. 344 licences made 73 percent of applications.
Are the biggest fumigators also the biggest pest control companies?
Almost never. Only one licence is in both the top 1 percent by pounds and the top 1 percent by applications in 2022, and three in 2023.
Why do earlier figures say the top tenth does about half the work?
Because they count reports or data rows, and a single monthly report can cover one application or thousands. Counting the applications the reports state gives four fifths. An earlier version of this report used rows and has been corrected.
How many licences are very small?
909 licences, 19.2 percent, reported fewer than ten structural applications or stated none in 2022. Low reported structural activity does not necessarily mean a small business.
Does a licence number mean one company?
Not verifiably. It identifies the entity filing the report, so this report says licence throughout and never company.
Does this tell me anything about revenue or market share?
No. Applications and pounds are activity measures. For what can be established about industry economics see our analysis of audited public filings.
Could this be done for other states?
Not currently. California is the only state that publishes structural pesticide use at this level of detail.
Where can I get the data?
The annual archives are free from the department at the link in the references. Filter to site code 10, group on the licence number and sum the application count once per report.
