I-275 Through St. Petersburg — St. Petersburg, Florida

Interstate 275 is the principal interstate highway serving St. Petersburg, Pinellas County's largest city, with a population of 260,646 as of the U.S. Census Bureau ACS 2023. The freeway enters the city from the north across Old Tampa Bay via the Howard Frankland Bridge, threads through the Pinellas Peninsula's urban core, and terminates at its southern end near downtown St. Petersburg before connecting onward to I-175 and the Sunshine Skyway approach. For the estimated 250,000 drivers who use the corridor daily, according to WUSF Public Media, I-275 is the dominant link between St. Petersburg and the broader Tampa Bay metropolitan region.

The corridor is in the midst of its most significant physical transformation in decades. A new Howard Frankland Bridge — replacing the structure built in the 1960s — opened to traffic in March 2025 at a cost of $865 million. Simultaneously, the Florida Department of Transportation is widening I-275 from 38th Avenue North to 4th Street North in St. Petersburg, adding tolled express lanes funded through the state's Moving Florida Forward initiative, with construction beginning in Summer 2025, as documented by FDOT and FDOT Tampa Bay.

I-275 enters St. Petersburg from the northeast after crossing Old Tampa Bay on the Howard Frankland Bridge. Moving southward through the city, the freeway passes through or adjacent to several distinct neighborhoods before approaching the downtown core. Key interchange points along the St. Petersburg segment include 38th Avenue North, Gandy Boulevard, 22nd Avenue North, and 4th Street North — the northern limit of the urban express lane project — as well as connections to I-175, which provides a short spur into the downtown waterfront district.

The geography of the Pinellas Peninsula shapes the corridor's role fundamentally. Because St. Petersburg is bounded by Tampa Bay to the north and east and the Gulf of Mexico to the west, as noted by the Advisory Council on Historic Preservation, I-275 and the parallel Gandy Bridge are among the only surface connections to Tampa and Hillsborough County. This bottleneck geometry means that congestion on I-275 — particularly at the Howard Frankland crossing — has regional consequences extending well beyond St. Petersburg city limits. The Gandy Bridge and the Sunshine Skyway provide alternative bay crossings, but neither carries an interstate designation, leaving I-275 as the primary high-capacity link.

Within St. Petersburg, the freeway also connects to surface arterials that serve employment and residential neighborhoods, including the 22nd Avenue North corridor and the 4th Street commercial spine, both of which carry significant local traffic volumes independent of the interstate.

The Howard Frankland Bridge carries I-275 across Old Tampa Bay, linking St. Petersburg to Tampa. The structure is the busiest of the three bay crossings — the others being the Gandy Bridge and the Sunshine Skyway approach — and its condition and capacity have long been central to transportation planning for both cities. Replacement of the aging original span was announced in 2013, and construction began in 2020, according to WUSF Public Media.

The new northbound span opened to traffic in March 2025 at a total cost of $865 million. WUSF reported the bridge carries approximately 250,000 drivers daily, making it one of the most heavily used crossings in the Tampa Bay region. The new structure was designed to accommodate tolled express lanes that connect to the broader express lane network being constructed on I-275 within St. Petersburg proper. Those express lanes on the bridge are already in place and operational as part of the new structure, forming the northern anchor of the ongoing widening project south of the crossing.

The original Howard Frankland Bridge, built decades earlier, had served beyond its intended design life, and state transportation officials had cited structural and capacity concerns as primary drivers for the replacement timeline. The 2013 announcement, 2020 construction start, and March 2025 opening mark a roughly twelve-year cycle from decision to ribbon-cutting for the $865 million project.

South of the Howard Frankland Bridge, FDOT is widening I-275 through a significant stretch of St. Petersburg as part of the state's Moving Florida Forward initiative, funded by a $4 billion General Revenue Surplus appropriation. The project, formally titled I-275 Widening from north of 38th Avenue N to north of 4th Street N, adds tolled express lanes to a corridor that previously lacked them, as documented by FDOT Tampa Bay and confirmed in FDOT's September 2023 construction timeline release.

The lane configuration differs by segment. From 38th Avenue North to south of Gandy Boulevard, the project adds two tolled express lanes in each direction. From Gandy Boulevard to 4th Street North, the configuration narrows to one express lane in each direction, as specified in the FDOT September 2023 release. FDOT scheduled construction to begin in Summer 2025. The express lanes are designed to connect directly to the express lane infrastructure already built into the new Howard Frankland Bridge, extending the network from the bridge southward through the central St. Petersburg corridor.

Beyond the lane additions, the project scope includes noise barrier construction and a new shared-use path along Ulmerton Road, according to FDOT Tampa Bay project documentation. The tolled lanes are variable-rate managed lanes, meaning toll rates adjust based on traffic conditions to maintain a minimum speed standard — a model consistent with other express lane projects in the Tampa Bay region.

As of August 2025, WUSF Public Media reported that no timeline had yet been established for extending the express lane network further south to connect with downtown St. Petersburg. Forward Pinellas MPO Division Manager Chelsea Favero was cited by WUSF as characterizing the project's connectivity goal — linking the bridge express lanes to the St. Petersburg urban core — as a longer-range planning objective without a confirmed completion date at that time.

The I-275 express lanes project includes a provision that transit vehicles are permitted to use the tolled express lanes, according to FDOT Tampa Bay. This provision connects the highway project to the broader transit landscape in St. Petersburg, which is served by the Pinellas Suncoast Transit Authority (PSTA). Allowing transit vehicles in the express lanes creates the possibility of faster, more reliable bus service along the I-275 corridor for routes operated by PSTA, though the specific service changes that may result from the construction project were not detailed in available FDOT documentation.

The SunRunner bus rapid transit line, launched in 2022 and documented by Business Observer Florida as the Tampa Bay region's first BRT line, operates along a separate east-west corridor — from downtown St. Petersburg to St. Pete Beach — and does not run on I-275 itself. However, the SunRunner demonstrates St. Petersburg's broader multimodal context: 50,000 jobs and 40,000 residents fall within a half-mile of the SunRunner route, illustrating the density that frames transit-freeway interactions in the city.

Mayor Kenneth Welch's 2026 State of the City address, covered by Tampa Bay Business and Wealth Magazine, confirmed that a year-round premium ferry service between downtown St. Petersburg and Tampa was agreed upon for a 2026 launch. While not a component of I-275 infrastructure, the ferry represents a parallel bay-crossing option that the city is developing alongside the highway capacity investments on the Howard Frankland corridor. The project also includes a new shared-use path along Ulmerton Road as part of the I-275 widening scope, adding a non-motorized facility to a corridor that has historically been designed exclusively for automobile and truck traffic.

Forward Pinellas serves as the metropolitan planning organization for Pinellas County and coordinates long-range transportation planning for the I-275 corridor, including the express lane extension project, as reported by WUSF Public Media. The MPO's role involves federally required transportation planning processes that set priorities for projects of the scale now underway on I-275, and Forward Pinellas officials have been the primary public voice characterizing the express lane project's connectivity goals and gaps.

Within the Tampa Bay regional context, the I-275 corridor connects to I-75 north of the bay in Hillsborough County, making it part of a multi-county freeway network that links Pinellas to Hillsborough, Manatee, and Sarasota counties. The Sunshine Skyway Bridge, which carries I-275 across lower Tampa Bay to the south, connects St. Petersburg to Manatee County and points south — a segment distinct from the Howard Frankland crossing and not part of the current widening project.

The Moving Florida Forward program's $4 billion appropriation, which funds the St. Petersburg express lane project, is a statewide initiative administered by FDOT, and the I-275 project in St. Petersburg is one of multiple concurrent projects in the Tampa Bay region. The convergence of the Howard Frankland Bridge replacement and the in-city widening project represents the most sustained capital investment in the I-275 corridor since the freeway's original construction, and WUSF reported in August 2025 that planners had not yet established a timeline for the final segment connecting the express lane network to the downtown St. Petersburg core — leaving the ultimate geographic extent of the project as an open planning question as of that date.