Business Buyer School Research · Full study · Version 2026.1

100 Industries Ranked by Acquisition Supply

The 100 Highest of 152 U.S. Industries on the Acquisition Supply Index

Business Buyer School 2026 Acquisition Supply Study, full study · Version 2026.1 · Published October 6, 2026 · Prepared October 6, 2026. These counts measure how many small firms exist, not how many are for sale. The top 100 is the 100 highest scores on the Acquisition Supply Index, which combines density, share and count of small firms; it is not a ranking by pool size.

Short version · Full study · Methodology · Data · About the school

Key Finding

Business Buyer School analysis of U.S. Census Bureau Statistics of U.S. Businesses data found that 89.4% of the 6.4 million U.S. employer firms had fewer than 20 employees in 2022, and that among 152 acquisition-relevant industries, Residential Building Construction, Offices of Real Estate Agents and Brokers, Personal Care Services and Automotive Repair and Maintenance scored highest on the Acquisition Supply Index, which combines how many small firms there are per 10,000 employees, their share of all firms and their count. The index is not a ranking by pool size alone. About 70% of firms with fewer than 20 employees have fewer than 5, so the pool of staffed firms a buyer would consider is much smaller. These counts measure how many small firms exist. They do not show that any of them is for sale.

Key Statistics

Business Buyer School calculated from SUSB 2022 that 89.4% of U.S. employer firms (5.72 million of 6.40 million) had fewer than 20 employees, equal to 421 small firms per 10,000 employees.
Business Buyer School calculated that 70% of those firms with fewer than 20 employees had fewer than 5.
Business Buyer School calculated that the median ranked industry had 86.7% of its firms under 20 employees and 464 small firms per 10,000 employees (Buyable Business Density).
Business Buyer School calculated that Buyable Business Density ranged from 77.7 (Electrical equipment makers) to 3584.1 (Real estate agent and broker offices) small firms per 10,000 employees.
Business Buyer School calculated that the largest pools of firms under 20 employees were Restaurants (341,443), Home builders (residential building construction) (201,496), Janitorial, landscaping and pest control (200,133), Management and technical consulting (194,796), HVAC, plumbing and electrical contractors (173,219).
Business Buyer School calculated that the largest pools of firms with 5 to 99 employees were Restaurants (289,301), HVAC, plumbing and electrical contractors (76,499), Dentists (74,220), Janitorial, landscaping and pest control (64,969), Offices of Physicians (54,677).
Business Buyer School calculated a Spearman rank correlation of -0.90 between the supply index and employees per firm: the index is largely a measure of how small an industry's typical firm is.
Business Buyer School calculated a Spearman rank correlation of -0.53 between the Acquisition Supply Index and the Report 2 Durability Score: industries with many small firms tend to have higher establishment exit rates.
Business Buyer School calculated a Spearman rank correlation of 0.14 between the supply index and the Report 1 Recession Resistance Score.
Business Buyer School calculated that 28 industries stayed in the top quartile and 28 in the bottom quartile under all six scoring methods (minimum pairwise Spearman 0.88).

Each statistic is a Business Buyer School calculation from official Census Bureau data; the Census Bureau is not responsible for the calculations.

What Is and Is Not Measured

Measured: employer firms by enterprise employment size in each 4-digit industry (Census SUSB 2022). A firm counts once in every industry where it has an establishment. Franchisees are separate firms and count as small even when part of a large brand.
Buyable Business Density: firms with fewer than 20 employees divided by industry employment, times 10,000. A supply-density indicator.
Not measured: businesses listed for sale, owner willingness to sell, price, profit, or whether a small firm is worth acquiring. Many firms with fewer than 5 employees are one-person practices with no transferable operation.
Mature-firm share: the brief planned a firm-age component. Public data carry firm age only at the sector level, so it was left out.
Owner age (Report 3) is shown as a separate overlay, not part of the main index, because it exists for only 123 of 152 industries and at ACS group level.

The Top 100

The study scores 152 industries; this report lists the 100 with the highest scores on the Acquisition Supply Index (density, share and count combined), rather than the 100 largest pools. Restaurants hold the largest pool of firms under 20 employees and rank 60 on the index. Business Buyer School scores (0 to 100, higher means a denser, more small-firm-heavy industry with a larger count of small firms) combine three percentile components across 152 ranked industries. Model A weights: Buyable Business Density 40, share of firms under 20 employees 20, count of firms under 20 employees 40.

The top 100

The top 100
Rank	Industry (NAICS 2017)	Confidence	Supply index (Model A)	Small firms per 10,000 employees	Firms under 20 employees (share)	Firms under 20 employees (count)	Firms with 5 to 99 employees	Employees per firm	Stability across models
1	2361 Residential Building Construction	High	98.5	2283.2	97.2%	201,496	42,078	4.3	stable highest supply quartile
2	5312 Offices of Real Estate Agents and Brokers	High	98.1	3584.1	98.9%	149,290	10,047	2.8	stable highest supply quartile
3	8121 Personal Care Services	High	94.8	1818.4	95.8%	135,200	42,203	5.3	stable highest supply quartile
4	8111 Automotive Repair and Maintenance	High	94.4	1492.4	95.9%	143,105	50,407	6.4	stable highest supply quartile
5	5411 Legal Services	High	93.6	1352.4	95.1%	160,064	42,599	7.0	stable highest supply quartile
6	6213 Offices of Other Health Practitioners	High	93.2	1372.9	95.0%	157,071	46,197	6.9	stable highest supply quartile
7	5416 Management, Scientific, and Technical Consulting Services	High	92.5	1198.7	95.1%	194,796	30,531	7.9	stable highest supply quartile
8	5311 Lessors of Real Estate	High	92.3	1610.6	95.6%	96,756	18,543	5.9	stable highest supply quartile
9	2383 Building Finishing Contractors	High	90.7	1390.6	94.0%	117,820	34,544	6.8	stable highest supply quartile
10	5414 Specialized Design Services	High	90.2	2786.1	97.6%	36,038	6,149	3.5	stable highest supply quartile
11	5242 Agencies, Brokerages, and Other Insurance Related Activities	High	88.2	942.1	96.4%	124,571	30,985	10.2	stable highest supply quartile
12	6212 Offices of Dentists	High	87.2	1099.8	94.2%	113,495	74,220	8.6	stable highest supply quartile
13	5617 Services to Buildings and Dwellings	High	86.9	950.0	92.9%	200,133	64,969	9.8	stable highest supply quartile
14	4453 Beer, Wine, and Liquor Stores	High	86.2	1585.7	96.6%	30,758	10,834	6.1	stable highest supply quartile
15	5412 Accounting, Tax Preparation, Bookkeeping, and Payroll Services	High	85.8	928.6	95.2%	114,312	30,671	10.3	stable highest supply quartile
16	8114 Personal and Household Goods Repair and Maintenance	High	85.3	2726.6	97.8%	21,043	4,057	3.6	stable highest supply quartile
17	8129 Other Personal Services	High	85.0	1279.2	94.3%	46,181	14,622	7.4	stable highest supply quartile
18	4251 Wholesale Electronic Markets and Agents and Brokers	High	84.1	1296.6	95.1%	32,420	6,670	7.3	stable highest supply quartile
18	5313 Activities Related to Real Estate	High	84.1	1067.6	93.2%	83,723	20,863	8.7	stable highest supply quartile
20	4539 Other Miscellaneous Store Retailers	High	83.3	1182.0	94.2%	42,513	14,730	8.0	stable highest supply quartile
21	5239 Other Financial Investment Activities	High	82.8	930.6	94.7%	57,740	12,038	10.2	stable highest supply quartile
22	2381 Foundation, Structure, and Building Exterior Contractors	High	81.6	1014.4	91.0%	93,665	35,763	9.0	stable highest supply quartile
23	4841 General Freight Trucking	High	81.5	816.2	93.9%	99,915	18,378	11.5	stable highest supply quartile
24	2389 Other Specialty Trade Contractors	High	80.3	977.0	90.4%	71,424	27,947	9.3	stable highest supply quartile
25	2382 Building Equipment Contractors	High	79.3	762.5	89.7%	173,219	76,499	11.8	moderate
26	6116 Other Schools and Instruction	High	78.5	1026.7	90.4%	48,630	23,159	8.8	stable highest supply quartile
27	4543 Direct Selling Establishments	High	78.4	1235.1	93.4%	23,974	6,981	7.6	stable highest supply quartile
28	5419 Other Professional, Scientific, and Technical Services	High	76.8	813.9	91.5%	63,112	24,033	11.2	stable highest supply quartile
29	4531 Florists	High	76.4	1959.9	96.9%	11,209	4,107	4.9	method-sensitive
30	8123 Drycleaning and Laundry Services	High	76.0	938.8	94.3%	23,238	7,619	10.0	stable highest supply quartile
31	4483 Jewelry, Luggage, and Leather Goods Stores	High	75.8	1250.2	96.8%	13,544	4,106	7.7	moderate
32	4541 Electronic Shopping and Mail-Order Houses	Medium	74.7	639.4	93.2%	49,913	13,007	14.6	moderate
32	4842 Specialized Freight Trucking	High	74.7	904.7	90.3%	45,915	15,023	10.0	moderate
34	4471 Gasoline Stations	High	73.4	576.5	93.1%	56,979	27,757	16.2	moderate
35	4452 Specialty Food Stores	High	72.8	1136.3	91.2%	18,685	8,621	8.0	moderate
36	5415 Computer Systems Design and Related Services	Medium	72.7	544.0	91.0%	115,692	29,360	16.7	moderate
37	5121 Motion Picture and Video Industries	High	72.5	765.0	94.6%	21,631	4,011	12.4	moderate
38	5418 Advertising, Public Relations, and Related Services	High	71.8	686.0	91.8%	32,053	9,211	13.4	moderate
39	4532 Office Supplies, Stationery, and Gift Stores	High	70.3	904.8	94.3%	15,328	5,610	10.4	moderate
40	6211 Offices of Physicians	High	70.1	489.0	89.0%	129,265	54,677	18.2	moderate
41	7224 Drinking Places (Alcoholic Beverages)	High	69.8	844.1	86.7%	33,886	23,005	10.3	moderate
42	8113 Commercial and Industrial Machinery and Equipment (except Automotive and Electronic) Repair and Maintenance	High	68.6	894.1	91.3%	18,703	6,898	10.2	moderate
43	5413 Architectural, Engineering, and Related Services	High	68.3	510.7	89.1%	84,927	31,619	17.5	moderate
44	4239 Miscellaneous Durable Goods Merchant Wholesalers	High	67.5	748.7	88.7%	25,254	9,989	11.8	moderate
45	4511 Sporting Goods, Hobby, and Musical Instrument Stores	High	67.2	565.2	93.3%	23,882	10,461	16.5	moderate
46	8122 Death Care Services	High	66.1	918.2	92.1%	13,145	6,922	10.0	moderate
47	2372 Land Subdivision	Medium	66.0	1861.3	94.7%	4,264	988	5.1	method-sensitive
48	4884 Support Activities for Road Transportation	Medium	65.8	938.5	91.7%	11,621	4,434	9.8	moderate
49	4853 Taxi and Limousine Service	High	65.6	1424.8	93.6%	6,753	1,619	6.6	method-sensitive
50	4422 Home Furnishings Stores	High	65.2	634.0	93.7%	15,671	6,562	14.8	moderate
51	8112 Electronic and Precision Equipment Repair and Maintenance	High	63.0	895.5	93.8%	9,470	2,647	10.5	moderate
52	6114 Business Schools and Computer and Management Training	Medium	62.8	1034.1	91.7%	8,483	2,227	8.9	method-sensitive
53	4461 Health and Personal Care Stores	High	62.6	369.2	91.7%	38,255	19,387	24.8	moderate
54	5615 Travel Arrangement and Reservation Services	High	62.5	672.8	94.0%	11,421	2,597	14.0	moderate
55	4413 Automotive Parts, Accessories, and Tire Stores	High	61.3	430.4	92.5%	24,083	11,756	21.5	moderate
56	7212 RV (Recreational Vehicle) Parks and Recreational Camps	Medium	61.1	1343.7	90.8%	6,583	2,428	6.8	method-sensitive
57	6244 Child Day Care Services	High	60.1	522.2	80.1%	50,451	36,828	15.3	method-sensitive
58	7139 Other Amusement and Recreation Industries	High	59.5	433.7	82.3%	56,896	33,742	19.0	moderate
59	4481 Clothing Stores	High	59.2	280.8	93.7%	31,992	12,228	33.4	moderate
60	2362 Nonresidential Building Construction	High	58.5	482.0	82.9%	33,435	19,586	17.2	moderate
60	7225 Restaurants and Other Eating Places	High	58.5	314.2	75.8%	341,443	289,301	24.1	method-sensitive
62	4249 Miscellaneous Nondurable Goods Merchant Wholesalers	High	58.0	557.3	86.7%	18,569	7,707	15.5	moderate
63	5223 Activities Related to Credit Intermediation	Medium	57.1	458.0	92.9%	14,990	3,540	20.3	moderate
64	4421 Furniture Stores	High	56.8	580.0	90.0%	11,441	5,863	15.5	moderate
65	5619 Other Support Services	High	56.8	532.4	88.7%	16,238	5,864	16.7	moderate
66	4442 Lawn and Garden Equipment and Supplies Stores	High	56.6	642.4	87.1%	11,495	6,647	13.6	moderate
67	4243 Apparel, Piece Goods, and Notions Merchant Wholesalers	High	56.0	655.1	88.0%	11,306	4,499	13.4	moderate
67	4431 Electronics and Appliance Stores	High	56.0	523.2	91.4%	11,503	4,927	17.5	moderate
67	7223 Special Food Services	High	56.0	341.0	89.9%	24,899	9,072	26.4	moderate
70	5322 Consumer Goods Rental	High	54.0	704.6	89.9%	7,791	3,042	12.8	moderate
71	4533 Used Merchandise Stores	High	53.8	547.1	88.4%	11,443	5,005	16.2	moderate
72	3231 Printing and Related Support Activities	High	53.1	467.3	85.2%	18,181	9,472	18.2	moderate
73	4238 Machinery, Equipment, and Supplies Merchant Wholesalers	High	53.0	391.8	81.1%	30,040	17,579	20.7	moderate
73	4451 Grocery Stores	Medium	53.0	214.5	87.6%	63,716	26,849	40.9	method-sensitive
75	3399 Other Miscellaneous Manufacturing	High	50.2	485.0	84.6%	12,216	6,258	17.4	moderate
76	5629 Remediation and Other Waste Management Services	High	49.7	560.4	85.4%	9,339	4,887	15.2	moderate
77	4885 Freight Transportation Arrangement	High	49.5	425.4	86.8%	13,754	5,673	20.4	moderate
78	3327 Machine Shops; Turned Product; and Screw, Nut, and Bolt Manufacturing	High	48.9	480.0	79.8%	17,078	11,620	16.6	moderate
79	4412 Other Motor Vehicle Dealers	High	48.2	558.2	82.5%	9,613	6,366	14.8	moderate
80	5614 Business Support Services	High	47.8	256.5	87.4%	19,593	7,626	34.1	moderate
81	4512 Book Stores and News Dealers	High	47.4	588.2	92.3%	2,996	1,246	15.7	method-sensitive
82	4244 Grocery and Related Product Merchant Wholesalers	High	46.8	268.9	82.9%	22,772	11,086	30.8	moderate
83	5323 General Rental Centers	Medium	46.1	957.8	87.2%	1,833	1,029	9.1	method-sensitive
84	4234 Professional and Commercial Equipment and Supplies Merchant Wholesalers	High	45.4	273.6	83.9%	18,279	8,457	30.7	moderate
85	6115 Technical and Trade Schools	High	45.3	579.9	84.9%	6,422	3,343	14.6	moderate
86	4441 Building Material and Supplies Dealers	High	44.8	214.2	84.1%	27,142	17,714	39.3	method-sensitive
87	7211 Traveler Accommodation	High	44.5	222.2	77.3%	38,557	29,326	34.8	method-sensitive
88	4542 Vending Machine Operators	Medium	43.8	604.9	91.3%	2,349	645	15.1	method-sensitive
89	3152 Cut and Sew Apparel Manufacturing	High	43.2	619.4	86.3%	3,240	1,613	13.9	moderate
90	7113 Promoters of Performing Arts, Sports, and Similar Events	Medium	43.0	427.6	88.3%	7,437	2,585	20.6	moderate
91	4232 Furniture and Home Furnishing Merchant Wholesalers	High	42.5	490.6	81.5%	8,145	4,423	16.6	moderate
92	5111 Newspaper, Periodical, Book, and Directory Publishers	High	41.7	338.5	86.6%	9,405	4,059	25.6	moderate
93	4236 Household Appliances and Electrical and Electronic Goods Merchant Wholesalers	High	41.5	270.7	82.2%	14,003	7,244	30.4	moderate
94	5191 Other Information Services	Medium	40.8	248.8	89.5%	9,726	2,935	36.0	moderate
95	3371 Household and Institutional Furniture and Kitchen Cabinet Manufacturing	High	40.8	368.2	85.4%	8,469	4,435	23.2	moderate
96	3149 Other Textile Product Mills	High	39.2	544.5	84.4%	3,144	1,639	15.5	moderate
97	3118 Bakeries and Tortilla Manufacturing	High	38.7	325.9	80.9%	9,932	6,440	24.8	moderate
98	4231 Motor Vehicle and Motor Vehicle Parts and Supplies Merchant Wholesalers	High	37.6	274.1	80.3%	11,438	6,032	29.3	moderate
99	4411 Automobile Dealers	High	37.6	211.9	68.9%	27,516	18,826	32.5	method-sensitive
100	5324 Commercial and Industrial Machinery and Equipment Rental and Leasing	High	37.0	360.7	83.1%	7,078	3,363	23.0	moderate

Ranks 101 to 152 (not shown) are the 52 industries with lower index scores, mostly lower small-firm density, led by manufacturing: Forging and stamping, Electrical equipment makers, Paint and coatings makers, Animal feed makers, Glass product makers, Other chemical product makers rank lowest. Lower score does not mean a small pool: 40 of these 52 industries have more firms under 20 employees than the smallest count shown in the top 100 (1,833), so check the count column in the data file before ruling an industry out. All 152 ranked industries and 15 unranked low-confidence industries are in the dataset.

A Better Lens for Buyers: Staffed Small Firms

Because the index rewards very small firms, here are the industries with the most firms that have 5 to 99 employees, the range where an operation exists that someone can take over:

A Better Lens for Buyers: Staffed Small Firms
Industry (NAICS 2017)	Firms with 5 to 99 employees	Firms under 5 employees	Staffed small firms as share of all firms	Supply index rank of 152
7225 Restaurants and Other Eating Places	289,301	155,149	64.2%	60
2382 Building Equipment Contractors	76,499	115,037	39.6%	25
6212 Offices of Dentists	74,220	45,904	61.6%	12
5617 Services to Buildings and Dwellings	64,969	149,120	30.2%	13
6211 Offices of Physicians	54,677	88,250	37.6%	40
8111 Automotive Repair and Maintenance	50,407	98,049	33.8%	4
6213 Offices of Other Health Practitioners	46,197	118,007	27.9%	6
5411 Legal Services	42,599	124,861	25.3%	5
8121 Personal Care Services	42,203	98,792	29.9%	3
2361 Residential Building Construction	42,078	164,915	20.3%	1
6244 Child Day Care Services	36,828	25,199	58.4%	57
2381 Foundation, Structure, and Building Exterior Contractors	35,763	66,528	34.7%	22

Supply Is Not the Same as Durability or Recession Resistance

Reports 1 and 2 ranked the same industries by recession resistance and durability. Industries with higher supply index scores tend to score lower on the Report 2 Durability Score (Spearman -0.53) and are unrelated to recession resistance (0.14). Where owner age is available (Report 3, 123 industries), it is also unrelated to supply (Spearman -0.11); adding it to the index (Model G) changes the ranking little on that subset (Spearman 0.94 with Model A).

Common Acquisition Targets

Common Acquisition Targets
Industry (NAICS 2017)	What is in it	Supply rank of 152	Firms with 5 to 99 employees	Small firms per 10,000 employees	Employees per firm	Owners 65+ (Report 3 group)	Recession resistance rank of 152 (Report 1)	Durability rank of 152 (Report 2)
2361 Residential Building Construction	Home builders (residential building construction)	1	42,078	2283.2	4.3	9.9%	120	148
8111 Automotive Repair and Maintenance	Auto repair and maintenance	4	50,407	1492.4	6.4	10.9%	68	72
5416 Management, Scientific, and Technical Consulting Services	Management and technical consulting	7	30,531	1198.7	7.9	18.7%	5	137
2383 Building Finishing Contractors	Finishing contractors (drywall, painting, flooring)	9	34,544	1390.6	6.8	9.9%	136	126
5242 Agencies, Brokerages, and Other Insurance Related Activities	Insurance agencies	11	30,985	942.1	10.2	17.6%	35	62
6212 Offices of Dentists	Dentists	12	74,220	1099.8	8.6	12.2%	33	23
5617 Services to Buildings and Dwellings	Janitorial, landscaping and pest control	13	64,969	950.0	9.8	7.1%	24	117
5412 Accounting, Tax Preparation, Bookkeeping, and Payroll Services	Accounting, tax and bookkeeping	15	30,671	928.6	10.3	23.1%	10	79
2381 Foundation, Structure, and Building Exterior Contractors	Foundation, framing, roofing and exterior contractors	22	35,763	1014.4	9.0	9.9%	123	123
2382 Building Equipment Contractors	HVAC, plumbing and electrical contractors	25	76,499	762.5	11.8	9.9%	92	57
8123 Drycleaning and Laundry Services	Dry cleaning and laundry	30	7,619	938.8	10.0	19.4%	126	109
7225 Restaurants and Other Eating Places	Restaurants	60	289,301	314.2	24.1	7.6%	60	97
3231 Printing and Related Support Activities	Printing	72	9,472	467.3	18.2	18.7%	137	56
6216 Home Health Care Services	Home health care	119	15,087	117.4	55.6	13.3%	15	86

Each row is a 4-digit industry group; HVAC cannot be separated from plumbing, or landscaping from janitorial or pest control, in these sources. Owner age is for the ACS industry group that contains the industry.

What Buyers Should Learn

A high index score is not a list of sellers. The counts show how many small firms exist, not how many can be bought.
Many "small firms" are one- and two-person operations. About 70% of firms under 20 employees have fewer than 5 employees. Use the staffed-firm counts.
Supply and durability tend to move in opposite directions. Industries with higher supply index scores tend to score lower on the Report 2 Durability Score (Spearman -0.53), which combines exit rate, firm shutdown, job destruction and volatility. This is a correlation across industries, not a finding about any one business.
Density favors tiny-firm industries. Real estate agent offices and home builders rank highest in part because their typical firm is a handful of people.
Supply says nothing about price or margin.
Industry results do not tell you about a particular firm.

Methodology

Sources: Census SUSB 2022 (firms, establishments and employment by enterprise employment size, 4-digit NAICS; the 2022 data are published on 2017 NAICS codes, matching the Report 1 universe) and Reports 1 to 3 of this series. Universe and confidence tiers are those of Report 1 (167 industries; 152 ranked, 15 unranked). Full formulas, red-team review and limitations: the methodology page.

Data Download

The dataset behind this study is on the data page: all 167 industry rows as CSV and JSON, with a checksum file, field notes and the reuse wording. A data license has not been published; short quotations with attribution and a link are welcome.

Sources

U.S. Census Bureau, Statistics of U.S. Businesses 2022: https://www.census.gov/programs-surveys/susb.html
Business Buyer School Reports 1 to 3 (version 2026.1) for the industry universe, confidence tiers, durability, recession resistance and owner age.

How to cite

Cite as: Business Buyer School, 100 Industries Ranked by Acquisition Supply (full study), https://businessbuyerschool.com/research/acquisition-supply-index/full-report/. Version 2026.1. Published October 6, 2026.

Data: Business Buyer School Acquisition Supply Dataset 2026, version 2026.1.

Please cite the website and the version number. Figures labelled "Business Buyer School calculated" or "Business Buyer School score" are original calculations from the public source listed above; the Census Bureau is not responsible for them.

A data license has not been published; short quotations with attribution and a link are welcome.

Take this into your own search

Industry research is context, not a verdict on any one business. These free parts of the school show how to use it.

Write your Buy Box: set the type of business, size and hard exclusions before you search.
Cleaning, landscaping and HVAC compared: how the same principles show up in three trades.
See the curriculum or start free with Business Buyer School.