Office Space for Lease in Ontario, CA Near Ontario Airport: Free Tenant Representation
I represent tenants, not buildings.
Javier Brown · MGR Real Estate, Inc. · DRE #01755491
Free Search of Every Available Office, All LandlordsCall Javier: (909) 641-0582 Text
Disclosure: Some buildings in this area are owned and managed by MGR Real Estate, Inc., my brokerage (DRE Corp. #01841921). On those buildings, MGR's own listing agent represents the landlord. I represent only the tenant. Javier Brown, DRE #01755491.
Looking for office space for lease in Ontario, CA? I represent tenants, not buildings. I search every available office near Ontario International Airport (ONT) for you, across every landlord, along Guasti Road, Concours Street, Inland Empire Boulevard and beyond. Options run from a small office for rent or an executive suite of about 900 square feet up to full floors of more than 30,000 square feet, and many are already built out. I set up the tours, compare your options side by side, and negotiate rent, tenant improvements and lease terms for you. My fee is typically paid by the landlord. The area sits by the I-10 and I-15, near Rancho Cucamonga, a central base for teams serving the whole Inland Empire. Call Javier Brown at (909) 641-0582 for today's available suites and a tour this week.
Orange County office space (Irvine, Costa Mesa, Orange)
Small offices, executive suites and full floors
Suites start around 900 square feet and go up to full floors of more than 30,000 square feet, including executive suites and small offices for rent in Ontario, CA. Many are already built out and ready to move in. Call (909) 641-0582 for today's list (text works too).
Why use a tenant rep for office space in Ontario?
- ✔ I work for you, not the landlord
- ✔ One free search across every building and landlord, including MGR-owned buildings
- ✔ Tours, side-by-side comparisons and lease negotiation (rent, TIs, terms)
- ✔ Landlord typically pays my fee
- ✔ Hablo español – full service in Spanish
How I Represent Tenants
- ✔ I represent only the tenant. I never represent the landlord on your deal.
- ✔ I show you buildings from every landlord in the market, not just MGR's.
- ✔ I tell you upfront when a building is owned and managed by MGR Real Estate, my brokerage. MGR owns and manages Empire Tower V, Waterside and Centrelake, and on those buildings MGR's own listing agent represents the landlord.
- ✔ My goal is the best terms for you: rent, improvements, flexibility and timing.
Office buildings near Ontario International Airport
Here are some of the buildings I can show you. Some are owned and managed by MGR Real Estate (see disclosure). I can also show you any other building in the market.
Asking rates: about $2.65 to $3.00 per SF per month, full service. Rates change, so call Javier Brown (909) 641-0582 for current pricing.
3800 Concours — Floor plans on request — call Javier
Empire Towers I–IV
Available: I 1,298–10,773 SF, II 1,639–17,096 SF, III ~2,995 SF, IV 10,704–36,566 SF (call to confirm)
Empire Towers, 3633 & 4141 Inland Empire Blvd and 3800 & 4200 Concours St, Ontario CA – Class A office campus, 400,976 SF in 4 buildings, minutes from Ontario Airport (ONT).
3633 & 4141 Inland Empire Blvd · 3800 & 4200 Concours, Ontario, CA
400,976 SF · Class A · 4 buildings
Available suites: I 1,298–10,773 SF · II 1,639–17,096 SF · III ~2,995 SF · IV 10,704–36,566 SF
Available (Oct 2026): 1,298–36,566 SF
Ontario Airport Tower
Available: suites about 909–9,935 SF (call to confirm)
Ontario Airport Tower, 2855 E Guasti Rd, Ontario CA – 6-story LEED Class A office tower, 148,000 SF, next to Ontario International Airport.
2855 E Guasti Rd, Ontario, CA
~148,000 SF · Class A · 6 stories · LEED Silver
Available suites: about 909–9,935 SF
Available (Oct 2026): 909–9,935 SF
One Lakeshore Centre
Available: 907–49,692 SF across both buildings (call to confirm)
One Lakeshore Centre, 3281 E Guasti Rd & 3450 Centrelake Dr, Ontario CA – Class A offices, 176,813 SF in 2 buildings, near ONT.
3281 E Guasti Rd & 3450 Centrelake Dr, Ontario, CA
176,813 SF · Class A · 2 buildings
Available suites: 907–49,692 SF
Available (Oct 2026): 907–49,692 SF
Lakeview Center I & II
Asking $2.85/SF/mo
Available: Suites 105 (2,029 SF), 120 (4,431 SF), 210 (3,267 SF) at $2.85/SF/mo (call to confirm). Suite 120 floor plan on request.
Lakeview Center I & II, 3257 & 3237 E Guasti Rd, Ontario CA – Class A offices, 106,345 SF, small suites near Ontario Airport.
3257 & 3237 E Guasti Rd, Ontario, CA
106,345 SF · Class A · 2 buildings
Available suites: Ste 105 – 2,029 SF · Ste 120 – 4,431 SF · Ste 210 – 3,267 SF
Available (Oct 2026): 2,029–4,431 SF
Empire Corporate Center
Available: suites about 1,549–6,186 SF (call to confirm)
Empire Corporate Center, 800 N Haven Ave, Ontario CA – 4-story office building, 80,000 SF, small offices for rent near ONT and Rancho Cucamonga.
800 N Haven Ave, Ontario, CA
~80,000 SF · 4 stories
Available suites: about 1,549–6,186 SF
Available (Oct 2026): 1,549–6,186 SF
Floor plans on request — call Javier
Empire Tower V
Empire Tower V, 3990 Concours St, Ontario CA – 5-story office building, 128,464 SF, built 2007, near Ontario Airport.
3990 Concours, Ontario, CA
128,464 SF · 5 stories · built 2007
Available suites: 943–33,892 SF
Owned & Managed by MGR
Available (Oct 2026): 943–33,892 SF
Waterside Center
Waterside Center, 3110 & 3200 E Guasti Rd, Ontario CA – office space, 159,418 SF in 2 buildings, by Ontario Airport.
3110 & 3200 E Guasti Rd, Ontario, CA
159,418 SF · 2 buildings
Available suites: 768–33,781 SF
Owned & Managed by MGR
Available (Oct 2026): 768–33,781 SF
Centrelake Plaza
Centrelake Plaza, 3401 Centrelake Dr, Ontario CA – 6-story office building, 114,420 SF, near Ontario International Airport.
3401 Centrelake Dr, Ontario, CA
114,420 SF · 6 stories
Available suites: 1,440–6,653 SF
Owned & Managed by MGR
Available (Oct 2026): 1,440–6,653 SF
Frequently asked questions
Do you represent these buildings?
No. I represent only the tenant. Some of these buildings are owned and managed by MGR Real Estate, my brokerage, and on those, MGR's own listing agent represents the landlord. I can show you those buildings and any other building in the market.
Does it cost me anything to use a tenant rep?
In most lease transactions, no. The tenant rep's commission is usually paid by the landlord or listing side under the lease commission agreement. Every deal is different, so I'll explain how it works on yours, in writing, before we start.
My lease is coming up for renewal. Can you help even if I want to stay?
Yes. I can compare your current building with other options and negotiate your renewal so you have real alternatives on the table. It helps to start well before your lease ends.
We need less space, or more. What are our options?
I can look at downsizing, expanding within your building, or moving, and compare the costs and timing of each. Your current lease terms matter, so bring a copy when we talk.
Can you help us get out of a lease early or sublease our space?
I can review your options, such as a sublease, an assignment, or negotiating an early exit with your landlord. What's possible depends on your lease, so I'll look at it with you first. I'm not an attorney; for legal questions, talk to a real estate attorney.
Should we lease or buy our office?
It depends on your budget, how long you plan to stay and your growth plans. I can lay out lease and purchase options side by side so you can decide.
How long does an office search take?
It varies with size, market and how much build-out you need. Starting 12 to 18 months before your lease ends usually gives you the most choices and leverage.
What sizes are available?
From small executive suites to full floors, depending on current vacancy. Call or text for today's list.
Can I tour this week?
Yes. Call me at (909) 641-0582 and I'll set up tours, usually within a day or two.
Do you speak Spanish?
Yes, Spanish is my first language.
Is there Class A office space near Ontario International Airport?
Yes. Empire Towers, Ontario Airport Tower, One Lakeshore Centre and Lakeview Center are Class A office buildings minutes from ONT, along Guasti Rd, Concours St and Inland Empire Blvd. Call (909) 641-0582 for current suites.
Do you have small offices or executive suites for rent in Ontario, CA?
Yes. Suites start around 900 SF, with some smaller spaces at times, up to full floors over 30,000 SF. Many come with existing build-outs.
Are these offices close to Rancho Cucamonga and the rest of the Inland Empire?
Yes. The buildings sit by the I-10 and I-15, near Rancho Cucamonga and central to the Inland Empire, with easy access to Ontario Airport.
Office space near Rancho Cucamonga and the Inland Empire
The buildings sit by the I-10 and I-15 near Rancho Cucamonga, in the heart of the Inland Empire, with easy access to Ontario International Airport. That makes them a central base for teams serving Ontario, Rancho Cucamonga and the wider Inland Empire.
Looking for office space? Work with an agent who represents only you.
Free Search of Every Available Office, All Landlords Text EmailCall Javier at (909) 641-0582. I represent tenants, not buildings.
Disclosure: Some buildings in this area are owned and managed by MGR Real Estate, Inc., my brokerage (DRE Corp. #01841921). On those buildings, MGR's own listing agent represents the landlord. I represent only the tenant. Javier Brown, DRE #01755491.
MGR Real Estate, Inc. · 3800 E. Concours St., Suite 350, Ontario, CA 91764 · jbrown@mgrrealestate.com
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