Chicago’s Biggest City Vendors: 10 Names, 30% Of Contract Payments

Chicago paid $5.72B on numbered contracts in 2025, spread across 1,882 payee names. Ten of those names took $1.73B of it — 30 cents of every contract dollar. In 2019, the same ten-name measure took 33 cents. Measured this way, the city’s reliance on its biggest contract payees has barely moved.

Payments dataset, City of Chicago data portal · calendar 2019 vs 2025 · retrieved August 7, 2026

What this page counts — and what it leaves out

The city’s Payments file carries the city’s vendor-payment records back to 1996, updated daily. It stores recent payments as dated rows and, in its own words, summarizes “total payment information … for each vendor and contract number for data older than two years.” We verified the two forms never overlap for the same vendor, contract, and year. The summarized years carry one more quirk that decides this page’s design: they contain no direct-voucher rows at all — the payments whose contract-number field holds the marker “DV” rather than a contract’s number. So every 2019-vs-2025 comparison here excludes the DV rows and runs on the contract-numbered payments both years record: $4.42B in 2019, $5.72B in 2025. The 2025 direct-voucher money — $4.94B more — appears in its own section, with no year-over-year comparison.

A “vendor” in this file is whatever name the check went to, printed here exactly as recorded — including other governments. The file offers no description of what any payment bought: besides a date and, on recent rows, a voucher number, its fields are a department name, a contract number, an amount, and a payee name — none of which says what the money purchased. This page therefore says who was paid and how much, and never what for.

The ten biggest contract payees of 2025

Payee, as the file records it$5.72B totalshare

BLUE CROSS & BLUE SHIELD2019: $404M$610M10.7%
F.H. PASCHEN S.N. NIELSEN & ASSOCIATES, LLC2019: $243M$177M3.1%
F.H. PASCHEN, S.N. NIELSEN & ASSOCIATES, LLC2019: $243M$155M2.7%
BOARD OF EDUCATION OF THE CITY OF CHICAGO2019: $41M$147M2.6%
CAREMARK INC2019: $85M$130M2.3%
TURNER PASCHEN AVIATION PARTNERSnot in the 2019 top 25$122M2.1%
AECOM HUNT / CLAYCO, A JOINT VENTUREnot in the 2019 top 25$122M2.1%
Clark-W.E. ONeil JVnot in the 2019 top 25$105M1.8%
CONSTELLATION NEWENERGY INC2019: $62M$92M1.6%
BIGANE PAVING COMPANYnot in the 2019 top 25$72M1.3%

BLUE CROSS & BLUE SHIELD is the largest single payee name in both years: $404M in 2019, $610M in 2025, paid almost entirely through the Department of Finance. Across the whole file, the fifty biggest payee names took 57.7 percent of 2019’s contract dollars and 57.0 percent of 2025’s — more than half in both years, and nearly unchanged.

One firm name, two spellings — why these shares are floors

Ranks two and three on the 2025 list are the same corporate name with and without a comma: “F.H. PASCHEN, S.N. NIELSEN & ASSOCIATES, LLC” and “F.H. PASCHEN S.N. NIELSEN & ASSOCIATES, LLC.” The two strings appear separately in both years. Combined they total $486M for 2019 — which would top that year’s list — and $333M for 2025. We rank names exactly as the file spells them and merge nothing, so every concentration figure on this page is a floor: cleaning up spelling variants could only push the top names’ shares higher.

Top-payee shares, department by department

Department (2025 contract payments over $50M)dept. totaltop payee’s share

DEPARTMENT OF FINANCEtop payee: BLUE CROSS & BLUE SHIELD$838M73%
DEPT OF BUSINESS & INFORMATION SERVICEStop payee: CDW GOVERNMENT, LLC.$97M72%
DEPT OF ASSETS INFORMATION AND SERVICEStop payee: CONSTELLATION NEWENERGY INC$160M58%
DEPARTMENT OF STREETS AND SANITATIONtop payee: ALLIED WASTE TRANSPORTATION INC$111M41%
DEPARTMENT OF PLANNING AND DEVELOPMENTtop payee: BOARD OF EDUCATION OF THE CITY OF CHICAGO$355M37%
DEPARTMENT OF FLEET AND FACILITY MANAGEMENTtop payee: GENUINE PARTS COMPANY$107M36%
CHICAGO DEPARTMENT OF TRANSPORTATIONtop payee: F.H. PASCHEN S.N. NIELSEN & ASSOCIATES, LLC$567M17%
DEPARTMENT OF WATER MANAGEMENTtop payee: PAN-OCEANIC ENGINEERING CO INC$337M16%
CHICAGO DEPARTMENT OF AVIATIONtop payee: TURNER PASCHEN AVIATION PARTNERS$1.05B12%
CHICAGO DEPARTMENT OF PUBLIC HEALTHtop payee: AIDS FOUNDATION OF CHICAGO$91M10%
DEPT OF GENERAL SERVICEStop payee: MANSFIELD POWER & GAS, LLC$245M10%
DEPARTMENT OF FAMILY AND SUPPORT SERVICEStop payee: ALL CHICAGO MAKING HOMELESSNESS HISTORY$386M8%

Three departments sent a majority of their 2025 contract dollars to a single payee name: the Department of Finance (73 percent to BLUE CROSS & BLUE SHIELD), the Department of Business & Information Services (72 percent to CDW GOVERNMENT, LLC.), and the Department of Assets, Information and Services (58 percent to CONSTELLATION NEWENERGY INC). At the other end, the Chicago Department of Aviation spent the most of any department, and its top payee took 12 percent. One listing needs its own flag: the BOARD OF EDUCATION OF THE CITY OF CHICAGO appears as a payee — No. 4 on the 2025 list — because the file’s “vendor” is any payee, governments included.

The other $4.94 billion: direct vouchers

Alongside the $5.72B in contract payments, 2025’s dated rows show $4.94B paid under the “DV” marker in the contract-number field — direct vouchers, which the file’s column notes describe as payments “for miscellaneous products and services.” The names on the largest direct-voucher payments read differently: pension and annuity funds, the county and state treasurers, and banks. These rows exist only for recent years — the summarization that produced 2019’s records dropped them — so no year-over-year comparison is possible, and this section describes 2025 alone.

Direct-voucher payee, as recorded$4.94B totalshare

MUNICIPAL EMPLOYEE PENSION FD$1.07B21.6%
COOK COUNTY TREASURER$713M14.4%
POLICEMENS A & B FUND$330M6.7%
AMALGAMATED BANK OF CHICAGO$309M6.3%
STATE OF ILLINOIS TREASURER’S OFFICE$239M4.8%
NATIONWIDE RETIREMENT SOLUTION$217M4.4%
BANK OF NEW YORK TRUST$187M3.8%
FIREMENS ANNUITY BENEFIT FUND$181M3.7%
U S BANK N A$169M3.4%
ZIONS BANK$138M2.8%

Known limits

These are payments made in a calendar year, not contracts awarded in it — a payment can land years after its contract was signed. The file assigns no purpose to any payment beyond a department and contract number, so nothing here says what any dollar bought. Payee names are unmerged, so shares are conservative floors. The 2019 figures are the file’s own summarized totals; we can check that they are internally consistent, but the underlying dated rows no longer exist in the dataset to re-add. The 2025 rows include 198 negative entries totaling −$466 thousand, which the year’s sums net out. Payments from 1996 through 2002 sit in a single rolled-up bucket the file labels “2002,” and this page never uses it.

Source City of Chicago Payments (s4vu-giwb), retrieved August 7, 2026; the dataset updates daily and notes that payments older than two years are summarized per vendor and contract.
Universes Summarized rows carry a bare year in the check-date field; dated rows carry MM/DD/YYYY. Calendar 2019 is fully summarized; calendar 2025 is fully dated. We verified no vendor-contract-year appears in both forms, in both directions, before comparing.
Contract universe All 2019-vs-2025 figures sum the amount column over rows whose contract number is not “DV” — for 2019 that is every row; totals, per-payee sums, and per-department sums are portal-side grouped queries, cached with the analysis.
Concentration Top-ten and top-fifty shares divide the summed payments of the ten and fifty largest payee names, as recorded, by the year’s contract-payment total. Names are not merged; the F.H. Paschen comma pair shows why that makes every share a floor.
Departments 2025 contract payments grouped by department name; the table covers the twelve departments over $50 million. Top-payee share divides the department’s largest payee sum by the department’s total.

Computed by KCM Desk from records retrieved August 7, 2026. If you spot an error, corrections come first.