Toronto's office market has struggled in the years since the pandemic emptied out commercial buildings across the globe, and while some cities have rebounded, a sustained lack of demand for new office space in Canada's financial heart threatens to keep several high-profile megaprojects on the back burner for years to come.

Demand for office space sunk to new lows in 2024, with the national vacancy rate soaring to its highest level in three decades during the second quarter of 2024, and the Greater Toronto Area office market not faring much better with its highest vacancy rate since the first quarter of 2020, when the entire world hit the pause button. 

With double-digit percentages of existing offices still sitting empty as 2024 draws to a close, the future of several proposed office towers that promised to radically shake up the Toronto skyline now hangs in the balance.

Here are the four most significant office towers that may be stuck in limbo for the foreseeable future.

The HUB

Oxford Properties made a splash back in 2018 with a proposed 60-storey, 1.4-million-square-foot commercial tower (since refined to 59 floors) intended to rise from the large parking lot at 30 Bay Street.

Proposed amid a high-flying commercial market, the design from U.K.-based architects Rogers Stirk Harbour + Partners promised a striking spin on the traditional glass box aesthetic Toronto has become all too familiar with, with exterior structural elements and a rooftop spire.

With a roof height of over 258 metres, the tower would rank as the city's 6th-tallest building if completed today — though its spire height of 304 metres would be taller than any completed building in Toronto as of late 2024.

Rogers Stirk Harbour + Partners

However, approaching seven years since The HUB was first announced, an anchor tenant has yet to be secured, and there seem to be no immediate plans in the cards for this new landmark.

Union Centre

An office tower has long been in the works for this site at 171 Front Street West, starting with a proposed 48-storey tower a decade ago in 2014, which resurfaced with a stunning new design from Danish architects Bjarke Ingels Group in 2019.

Developers Westbank Corp and Allied Properties REIT's current plan for the site would rise 54 storeys to a height of 298 metres, which would make it the second tallest building in Toronto and all of Canada if completed today.

Further planning approvals were granted for the project in 2022, but movement on the new tower has been otherwise idle for the past two years.

Bjarke Ingels Group

blogTO has sought comment from Westbank on the future of this development.

191 Bay

QuadReal Property Group first filed plans for a 64-storey office tower near King and Bay back in 2017.

Plans for what would be the third tower in the Commerce Court complex call for a 301-metre-tall behemoth designed by Hariri Pontarini Architects and DIALOG that would stand as the tallest building in Canada if completed today.

Aside from its standout height and landmark spire rising from its roofline, the project also filed updated plans in 2021 that introduced a new observation deck perched high above the cityscape that would rival the CN Tower.

Hariri Pontarini Architects

blogTO reached out to QuadReal for the developer's take on this project's viability in the years to come, and a representative explained that "We are not pursuing redevelopment of 191 Bay at this time."

Union Park

Oxford Properties has long been eyeing the Metro Toronto Convention Centre as a redevelopment opportunity, including a controversial scheme pitched in 2012 to bring a multi-tower casino complex to the heart of the city.

Plans for the ill-fated "Oxford Place" project were scrapped, paving the way for a new proposal that was filed in 2019 calling for a $3.5 billion, 4.3 million-square-foot complex that would bring four towers to the four-acre site.

Now known as Union Park, the mega-development would add sweeping curves to the Toronto skyline with towers reaching approximate heights of 303, 262, 210 and 164 metres, respectively — the tallest of which (like others on this list) would house 58 storeys of commercial space and rank as Canada's tallest building if completed today.

Designed by Pelli Clarke Pelli Architects with support from Toronto's own Adamson Associates, the complex will most likely only exist in the form of renderings for the foreseeable future until the office climate improves.

Pelli Clarke Pelli Architects

In addition to a request for comment about its Union Centre featured above, blogTO also reached out to Oxford Properties seeking comment on the developer's outlook for this project.

Despite the grim outlook for new office developments in today's market, developers have already begun to propose new plans for sites that previously included significant commercial components.

In 2024 alone, new plans were filed for projects at 310 Front Street West and 145 Wellington Street West, axing their previously proposed mixed-use development plans and resubmitting versions with residential space planned in place of offices.

Could similar residential resubmissions reignite plans for tall towers on these sites? Or will the office market spring back to life and create the demand necessary for these new titans to rise?

Only time will tell.