Methodology
How the leakage estimate is made
The counter on the front page shows an estimate of what US commercial real estate loses each year to errors in shared building cost (CAM) and operating-expense bills — about $7 billion a year, range $4–15 billion. It is a modelled estimate from published data, not a measurement, and not a figure about any Komod.ai client. This page sets out the arithmetic and every source.
The method, in six steps
- Denominator: 2025 operating expenditures for US office ($139.5 B), retail ($82.7 B) and industrial ($52.7 B) buildings in the 79 BOMA markets — BOMA International, 2026 Market Study (NCREIF expenses over CoStar inventory).
- Share billed to tenants: about 50 % office, 80 % retail, 90 % industrial, bracketed from public REIT filings (BXP Q4 2024 42 %; Regency Centers FY 2024 80 %; Prologis FY 2018 88 %). Billed pool ≈ $183 B.
- Gross reconciliation-error rate on billed amounts (tenants over-billed plus landlords under-billing): 4.0 % office, 4.5 % retail, 3.0 % industrial (range 2.5–8 %), bounded from published lease-audit findings (Deloitte 2010; Cresa; KBA; CyberLease; CPA Journal 2000) and vendor recovery benchmarks.
- Leakage = Σ (billed pool × rate) ≈ $7.2 B a year; low $3.9 B, high $14.3 B (about $19 B if scaled to national inventory).
- The counter shows the central figure × the fraction of the calendar year elapsed since 1 January (UTC). It is an estimate of the market, in both directions, not a measured loss and not a figure about any client.
- Full source table, arithmetic and limitations: Komod research report Annual US CAM / operating-expense recovery leakage (2026-09-21). Corrections welcome.
Sources
Type: P = primary (trade body, government, regulator, academic, audited filing) · A = audit-firm or advisory finding (practitioners' own files — the tenants who chose to audit) · V = vendor publication · R = press or secondary re-citation. All retrieved 2026-09-21.
| # | Publisher / document | Year | Type | Scope | Figure used | Link |
|---|---|---|---|---|---|---|
| 1 | BOMA International, BOMA 2026 Market Study (Leeds School of Business, Univ. of Colorado Boulder; CoStar inventory, NCREIF expenses) | 2026 (2025 data) | P | 79 BOMA US markets, private office/retail/industrial ≥ 25,000 sf | Operating expenditures $274.9 B, 35.4 B sf, $7.78/sf; office $139.5 B / 8,115 M sf; retail $82.7 B / 6,474 M sf; industrial $52.7 B / 20,765 M sf | Source |
| 2 | BOMA International, BOMA 2022 Office Market Study | 2023 (2022 data) | P | 85 BOMA markets, office ≥ 25,000 sf | Office operating expenditures $134.9 B, 8.6 B sf, $15.76/sf | Source |
| 3 | NAIOP Research Foundation, Economic Impacts of Commercial Real Estate, 2025 U.S. Edition (NCREIF per-sf costs × Newmark inventory) | 2025 (2024 data) | P | US existing commercial buildings (office, industrial, warehouse, retail) | Building-operations expenditures $532.5 B on 57.8 B sf ($9.21/sf) | Source |
| 4 | NAIOP, press release for the 2026 U.S. Edition | 2026 (2025 data) | P/R | US commercial + residential + institutional operations | Operations $752.4 B on 73.8 B sf (broader scope than #3; not used as denominator) | Source |
| 5 | U.S. Census Bureau, Economic Census / Service Annual Survey (FRED `REVEF53112ALLEST`) | 2022 | P | NAICS 531120 lessors of non-residential buildings, employer firms only | Revenue $155.1 B (2022); a floor, since most lessors are non-employer entities | Source |
| 6 | U.S. Census Bureau, Service Annual Survey (FRED `REARALEESTF353`) | 2022 | P | NAICS 53 real estate, rental and leasing, taxable employer firms | Total expenses $618.4 B (2022) — sector-wide, not a CAM pool | Source |
| 7 | Nareit, REIT Industry Tracker Q4 2025 | 2026 (2025 data) | P | All listed US equity REITs | NOI 2025: office $8.3 B, industrial $12.5 B, retail $20.8 B; all equity REITs $121.9 B (context; no expense line) | Source |
| 8 | IREM, Income/Expense IQ National Summary, 2024 Operating Data | 2025 (2024 data) | P | IREM/BOMA/NAA submitters | Total operating expenses: office $10.33/sf, industrial $3.83/sf | Source |
| 9 | Regency Centers Corp., Q4 2024 supplemental (full year 2024) | 2025 | P | Grocery-anchored shopping centres, US | Recoveries from tenants $345.1 M vs property operating expense $248.6 M + real estate taxes $184.4 M → 79.7 % recovered | Source |
| 10 | BXP, Inc., Q4 2024 supplemental (quarter) | 2025 | P | Class A office, US gateway markets | Recoveries $90.1 M vs operating $114.1 M + real estate taxes $101.1 M → 41.9 % recovered | Source |
| 11 | Prologis, Inc., Form 10-K for 2018 (quarterly data note) | 2019 | P | Logistics/industrial, mostly US | Rental recoveries $529.9 M vs rental expenses $600.6 M → 88.2 % recovered (last year the line was disclosed separately) | Source |
| 12 | Deloitte Financial Advisory Services, 2010 Lease Administration Benchmarking Survey (reported in a Practical Law lease-audit note) | 2010 | A | 209 executives at companies leasing commercial space | 77 % of tenants conduct lease audits/reviews (90 % of those with 100+ leases); about two-thirds report cost reductions; recoveries $0.50–$2.00+ per sf | Source |
| 13 | Deloitte, Commercial Lease Advisory Services page | 2026 | A | Deloitte engagements | 10,000+ lease audits over 23 years, $250 M+ savings (≈ $25,000 per audit) | Source |
| 14 | Cresa (Toronto), What Are Common Errors Uncovered During a Lease Expense Review | 2024 | A | Cresa tenant files (Canada; self-selected) | ~70 % of files examined contained errors | Source |
| 15 | KBA Lease Services, Lease Tips and case studies | undated | A | KBA practice (70,000 leases audited, 12,000 cases settled) | "Close to 90 % of leases have mistakes" | Source 1Source 2 |
| 16 | CyberLease LLC, Preliminary Reviews | undated | A | Large office tenants (audits recommended after screening) | Recoveries $2–$5 per rentable sf; "overwhelming majority of additional-rent billings are incorrect, but not all material" | Source |
| 17 | The CPA Journal, "Lease Compliance Review: An Emerging Trend" | 2000 | P/A | US commercial leases | "As much as 25 % of all lease-related billings contain some errors, usually in the landlord's favor"; 40 B sf leased | Source |
| 18 | Property Solutions / Kingston University, Service Charge Operating Report (SCOR) for Offices (reported by Property Week, 2012; Commercial News Media, 2014) | 2012, 2014 | P/A | 100 UK multi-let office buildings per year | 5 % (2012) and 6 % (2014) of buildings fully compliant with the RICS service-charge code | Source 1Source 2 |
| 19 | PredictAP, The $15 Billion Problem Hiding in Plain Sight (D. Stifter) | 13 Feb 2026 | V | US CRE | "$600–700 B rental income × 15–35 % CAM share = $90–200 B CAM market"; "40 % of reconciliations contain material errors"; "$5–15 B annual revenue leakage" | Source |
| 20 | Prophia, The $15 Billion Blind Spot | 2026 | V/R | US CRE | "$15 B a year", citing PredictAP; "3–5 % of occupancy costs" recovered by audits | Source |
| 21 | Kardin, Why 40 % of CAM reconciliations still get it wrong | 2026 | V/R | US CRE | Repeats "$5 to $15 billion" and "40 %" | Source |
| 22 | Springbord, How CAM Audits Help Tenants Control Real Estate Expenses and Take Charge of Your Expenses | Mar 2025 | V | Tenant CAM audits | Attributes "40 %" to Tango Analytics 2023 and "28 %" to JLL 2023; "15–20 % of billed CAM" recovered; a sister post attributes "30 %" to BOMA and "15–20 %" to Deloitte — the chain is internally inconsistent | Source 1Source 2 |
| 23 | Tango Analytics, CAM reconciliation and CAM audit blog pages | 2023–2025 | V | Retail tenants | No published study or dataset behind the "40 %" figure was found on Tango's site | Source 1Source 2 |
| 24 | CapVeri, CAM Leakage Benchmarks by Property Type; Recovery Ratio Analysis; CAM Reconciliation Cost | 2026 | V | Landlord portfolios (vendor benchmarks, method not published) | Landlord under-recovery 0.5–3.5 % of recoverable opex (office 1.0–2.5, retail 1.5–3.5, industrial 0.5–1.5, medical office 2.0–3.5); expected recovery ratios NNN office 85–95 %, FSG office 50–70 %, retail 80–90 %, industrial 90–98 %; tenant recoveries "3–8 % of audited charges"; notes the 40 % benchmark's "primary study is not publicly available" | Source 1Source 2Source 3 |
| 25 | Gable, Lease Audit [2026 Guide] | 2026 | V | Tenants | Professional CAM audits recover 3–5 % of annual occupancy costs | Source |
| 26 | MightyBot, LeaseMind product page | 2026 | V | Tenant reconciliations | "$5–10 B" CAM overcharges, "2 in 5" statements — labelled directional by the publisher | Source |
| 27 | LegalClarity, Commercial Lease Audit Rights | 2026 | R | US tenants | "30 to 40 percent" of statements contain errors; "median overcharge around 8 % of total CAM" where errors exist (unsourced) | Source |
| 28 | CoStar national reports (via broker distributions) | 2025 | P/R | US inventory | Office ≈ 8.4 B sf; industrial 19.4 B sf (CoStar National Index) | Source 1Source 2 |
| 29 | Florance, Miller, Peng, Spivey, Slicing, Dicing, and Scoping the Size of the U.S. Commercial Real Estate Market, Journal of Real Estate Portfolio Management | 2010 | P | US inventory | Office 12.1 B sf, industrial 23.9 B sf, retail 17.3 B sf, 84 B sf all commercial incl. multifamily (2010 basis) | Source |
Not found after searching: any BOMA, IREM, ICSC, NAIOP, CREW, NCREIF, Nareit, Big Four or peer-reviewed publication that states a US dollar total for CAM leakage; the "2023 Tango Analytics analysis" (40 %); the "JLL 2023 industry report" (28 %); the "Colliers" double-billing survey (20 %); the "National Lease Advisors study" (18 %). Each appears only as a re-citation.