When does rent start on a new Denver office lease?
Rent starts on the rent commencement date, which is often not the date the lease starts. Landlords prefer a fixed calendar date; tenants should tie it to substantial completion of the build-out, which in Denver depends on a building permit a general contractor who files there regularly puts at 8 to 12 weeks from submittal for a standard tenant improvement (Snyder Constructors, April 2026). Define the trigger, the outside date, and what happens when the permit runs late, or your free rent burns while the space is still a construction site.
Three dates, one lease, and only one of them costs you money
Most occupiers read a lease term as a single start date. It is usually three.
- Lease commencement. The date your obligations under the lease begin: insurance, compliance, and often the clock on your term.
- Possession or early access. The date you can get into the space to build, cable, and furnish.
- Rent commencement. The date base rent starts, after any abatement.
When those three line up, nobody notices. When the build-out runs long, the gap between them is where the money goes. A landlord's form lease will fix commencement on a calendar date and start the free rent period from it. If construction slips six weeks, the free rent you negotiated is spent on months you couldn't occupy.
Price it before you sign. As an illustration on asking rent, not a quoted deal: a 20,000 square foot lease at the metro average of $34.07 per square foot full service gross (CBRE, Q2 2026) runs about $13,100 a week. Six weeks of slippage against a fixed date is roughly $78,600 of rent or abatement for a space you cannot use. That is before any holdover premium at the building you're trying to leave.
The permit is the variable nobody negotiates
The single biggest swing in a Denver build-out schedule is not the contractor. It is the building department, and the Denver metro has a lot of them.
Snyder Constructors, a Colorado general contractor that files tenant improvement permits across the Front Range, published its 2026 read on actual project timelines (April 10, 2026):
| Jurisdiction | Standard commercial TI, plan review |
|---|---|
| City and County of Denver | 8 to 12 weeks submittal to permit; 6 to 10 weeks before first review |
| Aurora | 2 to 3 weeks |
| Lakewood | 3 to 5 weeks |
| Jefferson County | 3 to 6 weeks |
| Arapahoe County | roughly 2 months |
Those are one contractor's averages from its own projects, not a survey. Restaurants, medical, and assembly uses run longer, and every correction round adds time.
The city tells a better story, and it is also true. Denver's Community Planning and Development department told City Council that on-time permitting reached 88% so far in 2026, up from 82% in 2025, and that interior remodels now route through quick permits where scope allows (Denver Business Journal, September 23, 2026). "On time" measures review against the city's own targets. A contractor's clock measures from the day the drawings go in to the day the permit comes out. Both numbers can be right, and your lease should be written for the second one.
This is also why submarket choice changes the construction schedule, not just the rent. The Denver Tech Center straddles Denver, Greenwood Village, and Centennial, each with its own building department. Two suites a mile apart can sit in different permit queues. It belongs in the same comparison as commute, parking, and total occupancy cost when you weigh DTC against downtown.
Who carries the delay depends on who builds
Before you negotiate the date, settle who controls construction, because the risk follows control.
Landlord builds (turnkey or landlord work). The landlord hires the contractor, pulls the permit, and delivers finished space. Delay is the landlord's problem, so rent commencement should key off substantial completion of the landlord's work, and the lease should say what happens if it's late.
Tenant builds with an allowance. You hire the contractor and pull the permit. The landlord will argue any delay is yours, and on a pure allowance deal they're mostly right. Your protection is a build-out period measured from permit issuance or from delivery of the space in the agreed condition, not from lease signing.
Most Denver deals are a hybrid, and the TI allowance versus free rent trade-off is tangled up in it. A larger allowance with less free rent shifts more construction risk onto you. Price that before you pick the structure.
Six terms that keep the calendar honest
- Rent commencement keyed to substantial completion, defined properly. Substantial completion should mean the space can be lawfully occupied for your use: permit finaled or a certificate of occupancy (temporary is fine) issued, building systems serving the premises operating, and only punch-list items open that don't interfere with use. Holland & Knight's June 2026 guidance to tenants makes the same point: landlords want remedies to end at substantial completion, so make sure that term means the work needed for lawful occupancy is actually done (Holland & Knight, June 23, 2026).
- Free rent runs from rent commencement, not lease commencement. One sentence. It is the difference between abatement you use and abatement you lose.
- An outside date with teeth. If the space isn't delivered by a stated date, you get day-for-day rent credit, rising after a defined grace period, plus reimbursement of holdover costs at your current location. After a longer delay, you get the right to terminate and recover out-of-pocket costs.
- Narrow force majeure and tenant delay. Exclude routine permitting timelines, supply chain issues, and contractor performance from the landlord's force majeure, and require the landlord to give written notice of any claimed tenant delay within a few business days of the event, so it can't be reconstructed after the fact.
- A permit contingency on tenant-built deals. If you're building with an allowance in Denver proper, give the build-out period a floor measured from permit issuance, or extend rent commencement day-for-day for review delays beyond a stated number of weeks.
- Early access at no rent. Negotiate access for cabling, furniture, and IT during construction without triggering rent or commencement. It shortens the gap between completion and move-in by weeks.
Every one of these is easier to get before the letter of intent is signed than after the lease draft arrives. The landlord's form will not volunteer them.
One more date to watch on new construction
For new buildings, build-to-suits, and power-heavy industrial or lab space, the utility can set your occupancy date as easily as the building department. A Denver homebuilder has sued Xcel Energy alleging hookup delays pushed one project into foreclosure, and a Colorado Public Utilities Commission staff finding cited in the coverage says only one of the large commercial customers it interviewed received its system impact study on time (Hoodline, citing The Denver Post, September 2026). Those are allegations and staff findings, not court rulings. They are enough reason to tie rent commencement to energized, permanent power rather than a landlord's completion certificate.
Frequently asked questions
What is the difference between lease commencement and rent commencement?
Lease commencement is when your obligations under the lease begin; rent commencement is when you start paying base rent. They differ when there is a build-out period or free rent. In a Denver office lease, tie rent commencement to substantial completion of the space rather than a fixed date.
How long does a commercial tenant improvement permit take in Denver?
A Colorado general contractor puts a standard TI in the City and County of Denver at 8 to 12 weeks from submittal to permit in 2026, with faster timelines in Aurora and Lakewood (Snyder Constructors, April 2026). The city reports 88% on-time review against its own targets so far in 2026. Plan your lease around the contractor's clock.
Should free rent start at lease commencement or rent commencement?
At rent commencement. If abatement starts from a fixed commencement date and construction runs late, you spend free rent on months you can't occupy. Say it explicitly in the lease.
What happens if the landlord doesn't deliver my space on time?
Only what your lease says. A well-drafted lease sets an outside delivery date, gives day-for-day rent credit after it, reimburses holdover costs at your current space, and grants a termination right after a longer delay. Without those terms, most tenants have little recourse beyond a later rent start.
Does the jurisdiction really matter within the Denver metro?
Yes. Permit review for a standard tenant improvement can run 2 to 3 weeks in Aurora and 8 to 12 weeks in the City and County of Denver, based on one contractor's 2026 project experience. On a 20,000 square foot lease at metro average rents, that difference is tens of thousands of dollars.
Put the calendar in the lease, not in the landlord's hands
The rent commencement date is where construction risk turns into money. Tie it to substantial completion, make free rent run from it, set an outside date, and write the Denver permit clock into the schedule instead of hoping it cooperates. If your current lease expires on a fixed date, the math also tells you when to start the renewal or relocation process: early enough that a slow permit is an inconvenience, not a holdover.
If you're working through a lease decision in Denver, whether that's a renewal, a relocation, or a footprint question your CFO is pushing on, I'm happy to run the numbers with you. Schedule a conversation.
About Brian McCririe
Brian McCririe is Executive Managing Director of SVN | Denver Commercial and National Council Chair for Occupier Services across the SVN network. After 25 years representing tenants and investors across global markets, he now focuses on the Denver Metro area helping companies navigate leases, acquisitions, and the gap between what landlords offer and what occupiers deserve. He leads one of the metro's top tenant rep practices and writes about the deals, decisions, and market shifts that matter to corporate real estate leaders.
