What is the banquet capacity of Oak Brook Ballroom (A-H) at Chicago Marriott Oak Brook?

Oak Brook Ballroom (A-H) seats up to 1,000 guests in a banquet layout.

How many people fit in Oak Brook Ballroom (A-H) theater-style?

Oak Brook Ballroom (A-H) holds up to 1,200 guests in a theater setup.

How many event spaces does Chicago Marriott Oak Brook have?

Chicago Marriott Oak Brook has 26 event spaces totaling 48,014 sq ft.

Chicago Marriott Oak Brook — Event Spaces & Capacities

1401 W 22nd St, Oak Brook, IL 60523

Planning an event in Oak Brook? Chicago Marriott Oak Brook has 26 function rooms across 48,014 sq ft4,461 m² of function space. The largest room, Oak Brook Ballroom (A-H), hosts up to 1,250 guests. Capacity figures for every setup style are listed per room below.

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Floor plans

Detailed floor plans for Chicago Marriott Oak Brook are published on the venue’s official site.

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Room capacities & dimensions

Room capacities and dimensions for Chicago Marriott Oak Brook
Space	Sq ft / m²	Ceiling	Banquet	Theater	Classroom	Reception	Conference	U-Shape
Burr RidgePlan this room →	336 sq ft31 m²	10 ft3 m	—	—	—	—	12	—
Elmhurst 1Plan this room →	396 sq ft37 m²	10 ft3 m	33	41	22	44	13	18
Elmhurst 2Plan this room →	556 sq ft52 m²	10 ft3 m	46	58	31	61	18	18
Elmhurst 3Plan this room →	615 sq ft57 m²	10 ft3 m	51	64	35	68	20	18
Elmhurst 4Plan this room →	640 sq ft59 m²	10 ft3 m	53	67	36	71	21	18
Foyer & Salons E-H (combined)Plan this room →	3,600 sq ft334 m²	10 ft3 m	320	300	200	250	—	55
La GrangePlan this room →	850 sq ft79 m²	10 ft3 m	60	60	45	50	24	20
LombardPlan this room →	625 sq ft58 m²	10 ft3 m	50	50	26	45	24	20
Marquis RoomPlan this room →	2,100 sq ft195 m²	8 ft2.4 m	160	150	80	200	45	40
Oak Brook Ballroom (A-H)Plan this room →	11,040 sq ft1,026 m²	17 ft5.2 m	1,000	1,200	700	1,250	—	—
Oak Brook RoomPlan this room →	1,100 sq ft102 m²	—	40	—	—	—	—	—
Salon APlan this room →	3,600 sq ft334 m²	17 ft5.2 m	320	350	200	350	—	55
Salon BPlan this room →	1,008 sq ft94 m²	17 ft5.2 m	80	120	70	90	35	30
Salon CPlan this room →	1,008 sq ft94 m²	17 ft5.2 m	80	120	70	90	35	30
Salon DPlan this room →	1,825 sq ft170 m²	17 ft5.2 m	120	225	100	200	55	50
Salon EPlan this room →	550 sq ft51 m²	10 ft3 m	40	45	20	40	20	20
Salon FPlan this room →	550 sq ft51 m²	10 ft3 m	40	45	20	40	20	20
Salon GPlan this room →	550 sq ft51 m²	10 ft3 m	40	45	20	40	20	20
Salon HPlan this room →	350 sq ft33 m²	10 ft3 m	20	20	15	20	10	15
Salons A-D (combined)Plan this room →	7,440 sq ft691 m²	17 ft5.2 m	640	900	500	1,000	—	—
Salons B & C (combined)Plan this room →	2,015 sq ft187 m²	17 ft5.2 m	160	250	120	225	60	55
Salons B, C & D (combined)Plan this room →	3,840 sq ft357 m²	17 ft5.2 m	320	450	290	575	—	—
Villa ParkPlan this room →	468 sq ft43 m²	10 ft3 m	—	—	—	—	14	—
WestchesterPlan this room →	676 sq ft63 m²	10 ft3 m	50	50	26	45	24	20
WheatonPlan this room →	676 sq ft63 m²	10 ft3 m	50	50	26	45	24	20

Additional spaces (dimensions only) (1)

Additional spaces with published dimensions only at Chicago Marriott Oak Brook
Space	Sq ft / m²	Ceiling
Ballroom FoyerPlan this room →	1,600 sq ft149 m²	12 ft3.7 m

Figures from published venue data; blank cells mean the venue hasn’t published that number. Verify final counts with the venue.