Stranded at the Dock: How Port Congestion Is Quietly Draining US Importer Margins

For years, the conversation around US import costs focused on tariffs, freight rates, and supplier negotiations. Yet a quieter and increasingly expensive problem has embedded itself into the operational fabric of American supply chains: the inability to secure berth space at major gateway ports when it is actually needed.

The vessels arrive. The cargo is aboard. But the dock is occupied, the terminal is saturated, and the clock—measured in demurrage fees that accrue by the day—has already started running. What began as a pandemic-era anomaly has matured into a persistent structural reality at several of the country's highest-volume import gateways.

The Anatomy of a Berth Bottleneck

The United States moves the overwhelming majority of its containerized imports through a relatively small number of major port complexes. The San Pedro Bay ports of Los Angeles and Long Beach alone handle roughly 40 percent of all US container imports. The Port of New York and New Jersey, the Port of Savannah, and the Port of Houston collectively absorb much of the remainder. This concentration creates a fragile system: when volume surges, when labor disruptions emerge, or when vessel scheduling clusters—as it routinely does—congestion cascades rapidly.

Berth availability is determined not merely by physical space but by a confluence of terminal operating capacity, crane availability, chassis supply, and drayage driver scheduling. A shortfall in any one of these variables can render an otherwise available berth functionally inaccessible. When a vessel is forced to anchor offshore awaiting its turn, the cargo aboard it is simultaneously triggering contractual demurrage clocks at the terminal and creating downstream disruptions at warehouses, distribution centers, and retail replenishment cycles.

The financial exposure is not trivial. Demurrage charges at major US ports currently range from $75 to $250 per container per day after the allotted free time expires, with detention fees for unreturned equipment adding further layers of cost. For an importer moving fifty containers through a congested terminal on a delayed vessel, a week's worth of charges can represent tens of thousands of dollars in unplanned expenditure—expenditure that rarely appears in procurement cost models because it is classified as a logistics exception rather than a structural cost.

The Hidden Multiplier: Working Capital Erosion

The direct fees are damaging enough. But experienced supply chain professionals understand that the more consequential impact of port congestion operates at the level of working capital.

When goods are delayed at the terminal, inventory that was expected to arrive and be sold within a defined window instead sits in limbo. Retailers and distributors who have already committed to shelf space, promotional calendars, or customer delivery windows face a compounding problem: the inventory is unavailable, but the financial obligation to the supplier has often already been triggered. The result is a gap—sometimes measured in weeks—where capital is deployed but no revenue is being generated against it.

For businesses operating on thin margins or relying on just-in-time replenishment models, this working capital erosion can be more damaging than the demurrage charges themselves. It is also far harder to quantify in real time, which is precisely why it tends to be underestimated until it manifests as a cash flow problem.

Terminal Congestion Fees: The Cost That Rarely Makes the Headline

Beyond demurrage, many importers have encountered a newer category of charge: terminal congestion surcharges levied by ocean carriers and terminal operators during periods of peak strain. These fees, which can range from $100 to $1,000 per container depending on the carrier and the route, are often embedded in rate adjustments or peak season surcharges that shippers accept without fully modeling their cumulative impact.

The opacity of these charges is a recurring frustration among US importers. Unlike tariffs, which are codified and publicly available, congestion-related surcharges are frequently applied with limited advance notice and inconsistent justification. Importers who do not maintain active freight audit processes—reviewing carrier invoices against contracted rates and applicable surcharge schedules—routinely absorb costs they are not actually obligated to pay.

The Strategic Pivot: Rethinking Port of Entry

The most forward-looking US importers are not simply accepting congestion as an unavoidable cost of doing business through major gateways. They are actively redesigning their port-of-entry strategies to distribute risk and recover margin.

Smaller, underutilized ports have emerged as genuinely competitive alternatives for specific cargo profiles and regional distribution patterns. The Port of Portland in Oregon, the Port of Wilmington in North Carolina, the Port of Mobile in Alabama, and the Port of Baltimore—each historically overshadowed by larger neighbors—offer meaningfully shorter vessel turnaround times, lower terminal dwell periods, and in some cases, more predictable berth scheduling.

The calculus is not always straightforward. Smaller ports may offer fewer direct service calls from major shipping lines, potentially requiring transshipment or inland repositioning that adds its own cost and transit time. However, for importers whose distribution footprint is regionally concentrated, or whose cargo is not time-sensitive enough to justify premium gateway pricing, the arithmetic often favors the alternative.

Some importers have adopted a hybrid port strategy: routing standard replenishment cargo through secondary gateways while reserving major port relationships for time-critical or high-value shipments. This approach distributes exposure, reduces average dwell time across the portfolio, and creates negotiating leverage with terminal operators who recognize that volume is no longer captive.

Negotiating from a Position of Knowledge

Effective port strategy is as much a negotiation discipline as it is a logistics function. Importers who engage terminal operators, freight forwarders, and ocean carriers with detailed data on their cargo velocity, container volumes, and dwell time history are consistently better positioned to negotiate favorable free-time allowances, priority berth access arrangements, and reduced congestion surcharge exposure.

The same principle applies to contracts with third-party logistics providers. Agreements that do not explicitly address port delay liability, demurrage pass-through terms, and congestion surcharge notification requirements leave importers exposed to costs that a well-structured contract would either cap or eliminate.

Building this kind of commercial intelligence requires investment in freight audit capability and active carrier relationship management—functions that are often deprioritized in leaner logistics operations but that pay disproportionate dividends during periods of port stress.

Structural Pressure Is Not Going Away

US port infrastructure investment has accelerated in recent years, with federal funding directed toward terminal modernization, berth deepening, and equipment upgrades at several major gateways. These improvements will expand capacity over time. But infrastructure development operates on timelines measured in years, while import volume and vessel size continue to grow at a pace that consistently outstrips available berth capacity.

For US importers, the practical implication is clear: port congestion cannot be treated as a temporary disruption to be absorbed and forgotten. It is a recurring structural cost that demands the same analytical rigor applied to tariff strategy, carrier selection, and inventory planning.

The companies that recognize this earliest—and build port diversification, freight audit discipline, and contract precision into their supply chain architecture—will recover margins that their competitors continue to leave stranded at the dock.