Del Mar Heights Office Real Estate Asking Rents Surge 15–20% Despite 19–22% Availability, Hughes Marino Warns Tenants

SAN DIEGO — Asking rents in the Del Mar Heights office real estate market have risen 15–20% over the past year even as availability rates have remained elevated between 19% and 22% for three consecutive years, according to a market commentary published June 8, 2026, by tenant representation firm Hughes Marino. The analysis, authored by David Marino, argues that the pricing surge is disconnected from conventional supply-and-demand dynamics.

Elevated Asking Rents Amid High Availability

According to Hughes Marino, only one project in Del Mar Heights is currently asking below $4.50 per square foot plus electricity — 12555 High Bluff at $4.25 per square foot — while most asking rents range from $4.95 to $6.15 per square foot. Despite those figures, the firm notes that office space availability in the submarket has trended between 19% and 22% for the last three years, a rate Hughes Marino describes as one of the higher availability rates in San Diego County, exceeding those of Mission Valley, Sorrento Mesa, UTC, and the I-15 corridor.

The average time on market for office space in Del Mar Heights has reached a four-year high of 16 months, and many suites have been listed for more than two years, the firm reports. Market statistics cited in the commentary were provided by CoStar Group.

"From an economic fundamentals standpoint, the Del Mar Heights market is frozen in place, arguably getting worse when time on the market is considered… yet prices in the last year are up 15–20%," David Marino wrote in the commentary.

Three Factors Driving Office Real Estate Price Increases

Anchoring Off One Paseo

Hughes Marino identifies Kilroy Realty Corporation's One Paseo mixed-use project as the first driver of elevated asking rents. One Paseo is described as 100% leased and commands asking rents of $6.50–$7.00 per square foot when space becomes available, typically generating competitive bidding. The firm contends that other Del Mar Heights landlords have used One Paseo as a pricing anchor despite offering older office buildings constructed 20–40 years ago that the commentary says do not compare in location, amenities, quality, or desirability.

Abnormal Ownership Concentration

The second factor identified by Hughes Marino is an unusually high concentration of office property ownership. Excluding medical office and biotech wet lab buildings, Kilroy Realty controls approximately 37% of the Del Mar Heights office market by square footage, American Assets holds 13%, and the Irvine Company owns 10%. Combined, those three landlords account for roughly 60% of the submarket — a concentration the firm describes as "highly exceptional for any office market in the United States."

Hughes Marino states that full information sharing among large landlord brokerage firms allows building owners to move in lockstep on pricing, though the commentary stops short of characterizing the activity as formal collusion. "Rather, these landlords all have full information from the big landlord brokerage firms that share what each landlord is doing with the other building owners, and then each follows suit accordingly," David Marino wrote.

Abnormal Landlord Listing Broker Concentration

The third factor cited is the concentration of landlord listing broker market share. According to Hughes Marino's analysis, CBRE and Cushman & Wakefield each represent approximately 36% of the landlord listing market by square footage — a combined 72% — while Colliers holds an additional 12%. Together, those three firms account for 84% of all listings in the submarket, excluding medical office and biotech wet lab space. The Irvine Company conducts its own leasing through in-house brokers.

The commentary argues that the absence of regulatory oversight of the landlord brokerage industry allows brokers to share comparable lease data and other tenant information across competitive building owners, enabling market participants to move asking rents regardless of whether underlying supply-and-demand conditions support the increases.

Available Options for Del Mar Heights Office Tenants

Despite elevated asking rents, Hughes Marino notes that multiple options exist across a range of size requirements in Del Mar Heights. The firm's analysis includes a breakdown of available suites by square footage range, illustrating that tenants in multiple size categories have numerous choices in the current market.

The commentary warns, however, that tenants — particularly those approaching lease renewals — often lack the market knowledge to identify what constitutes a competitive deal. "With inflated asking rents, tenants don't fully understand what a good deal looks like," David Marino wrote. "As each uninformed and innocent Del Mar Heights tenant signs a lease at a new incremental high, and that comparable is shared with landlords and the brokerage community that supports them, the notion of rising rents becomes a self-fulfilling prophecy."

Hughes Marino's Guidance for Commercial Tenants

Hughes Marino recommends that office real estate tenants engage dedicated tenant representation firms to counteract what it characterizes as information asymmetry between tenants and landlords. The firm advises tenants to avoid working directly with landlords or with any broker that also represents building owners, citing inherent dual-agency conflicts of interest.

The commentary frames the Del Mar Heights situation as illustrative of broader dynamics affecting commercial tenants nationally, noting that tenants are not collectively organized and must navigate negotiations against landlords and their proxy listing brokers without equivalent access to market data.

Hughes Marino is a tenant representation firm. The Del Mar Heights market commentary was published on the firm's San Diego blog on June 8, 2026.