Ocean Service Contract vs Spot Rate: What You Are Actually Buying

Two quotes for the same box, three months apart

In February your carrier offers 2,400 USD per 40-foot container from Ningbo to Los Angeles for the coming contract year, against a commitment of 600 boxes. You sign. By July your forwarder is showing spot at 1,700 USD and the signature looks expensive. Twelve months later the market turns, spot runs at 4,600 USD, your competitor cannot get a slot for three weeks, and the same contract saves you several times what you thought you had lost.

Both readings are framed wrong. An annual commitment is not bought like a rate. It is bought like variance cover and like access priority, and judging it against today's spot number is like judging fire insurance on the fact that the building did not burn. What follows is what the document actually binds, where the asymmetry sits that most importers never price, and how to decide with a model instead of with market sentiment.

What a service contract actually binds

In the US trades the instrument is legally defined. The Shipping Act (46 U.S.C. § 40502) describes a service contract as a written agreement between a shipper — or a shippers' association — and an ocean common carrier, under which the shipper commits to a minimum quantity (the MQC) over a fixed period and the carrier commits to a rate and a defined service level: space, frequency, port rotation, transit time. Those contracts are filed with the Federal Maritime Commission. Outside the US trades — Asia-Europe, Asia-Mediterranean, intra-Asia — no filing obligation exists. The equivalent is a named-account rate, a nominative quotation valid for a period, and contractual discipline rests entirely on what the parties bothered to write down.

The pivot of the document is not the rate. It is the MQC, the only genuinely quantified obligation on the shipper's side, and it carries a sanction: liquidated damages or dead freight pro rata on the shortfall. Which produces a rule that is simple and rarely applied — never commit more than 60 to 70 percent of forecast volume. An import forecast almost never errs on the high side, and the shortfall exposure is asymmetric.

The rate is guaranteed, the space is not

This is the clause most contracts deliberately leave soft. The document fixes a price; it reserves no capacity unless an allocation clause says otherwise. In a tight market the consequence is arithmetic: a contracted box at 2,400 USD earns the carrier less than one sold the same day at 5,500 USD, and the arbitrage shows up as rolled cargo — your load stays on the terminal, pushed one or two sailings. The contract protected the price in precisely the market where price had stopped being the problem.

The fix is a clause, not a relationship. Three formulations are worth insisting on: an allocation commitment stated in boxes per week or per sailing rather than as an annual total; a symmetrical penalty that bites the carrier for rolling as it bites the shipper for shortfall; and a notice period before any change of rotation or transit time. The Ocean Shipping Reform Act of 2022 strengthened the shipper's hand by constraining unreasonable refusal to deal and widening access to the Federal Maritime Commission complaint process, but a statute does not substitute for a clause. Guaranteed-space products sold at a premium by the major carriers typically run a few hundred dollars per container — an order of magnitude that varies by trade and season. That looks expensive only to someone who has never costed a month of stockout.

Contract, spot, or index: the third term

Contract versus spot is a false binary. A third family has been growing since 2021: the index-linked contract, repriced periodically against a published benchmark — the SCFI from the Shanghai Shipping Exchange, Drewry's World Container Index, Xeneta's XSI, the Freightos FBX — inside a floor and a ceiling. You keep the volume commitment and the access priority, you drop the directional bet, and above all you remove the incentive to walk away from the contract, which is what damages the relationship in both directions.

That last row covers most mid-market US and UK importers and nearly every Indian exporter shipping under 100 TEU. Riding a forwarder framework contract is not a downgrade — it is the only route to a volume rate at that scale, and in the US trades it has its own regulatory basis in the NVOCC Service Arrangement and Negotiated Rate Arrangement regimes (46 CFR 531 and 532). Partner selection criteria are set out in our guide to choosing a freight forwarder.

Three worked decisions

The rates below are working assumptions used to show the method, not market quotations: container freight can move more than 100 percent in six months. Re-run the structure with your own numbers.

Example 1 — 600 FEU a year, Ningbo to Los Angeles. Contract at 2,400 USD, expected average spot at 2,150 USD but widely dispersed. In expectation the contract costs 600 x 250, or 150,000 USD more. In the high scenario, with spot averaging 4,000 USD, it saves 960,000 USD. Paying 150,000 USD of expected value to cover a 960,000 USD exposure is rational if your selling prices are set for the season and cannot absorb a freight shock. If you pass freight through line by line, the arithmetic reverses — your buyer is carrying the variance and you have no reason to insure it.

Example 2 — 40 FEU a year, Nhava Sheva to Felixstowe. The volume sits well below any direct MQC a carrier would write. The real question is which framework contract to ride. A forwarder with a volume agreement on the India-Europe trade will typically land 8 to 15 percent under public spot — an order of magnitude, not a promise — and, more valuably, hold the same transhipment service so transit time stops moving. One missed retail window costs more than a year of that percentage.

Example 3 — the clause that outweighs the rate. Two offers on Shanghai to Savannah: 2,550 USD with 5 days of free time at destination, or 2,690 USD with 10 days. The visible gap is 140 USD. If your customs clearance and drayage realistically take 8 days on that lane, the cheaper offer triggers 3 days of demurrage per box, at a daily tariff that commonly exceeds 150 USD once past the first tier. The cheap offer costs roughly 310 USD more per container, and the rate-only comparison picked the wrong winner. The full mechanism is in our article on demurrage and detention charges.

What to read before the rate

Rate scope. An all-in rate and a base-plus-surcharge rate are not comparable numbers. Bunker and currency adjustments, peak season surcharges, congestion or war risk surcharges and general rate increases can stay floating inside an otherwise signed contract, which is the leading source of mid-year increases people did not see coming. Ask for the closed list of inclusions and the formula for everything else. Each line item is broken down in our guide to BAF and CAF surcharges.

The calendar. Transpacific contracts traditionally run 1 May to 30 April, with the negotiating season clustering around the industry conferences in late winter; Asia-Europe contracts traditionally run on the calendar year. In both cases the useful negotiation happens two to three months before expiry, while the carrier is still building its book — not in the first weeks of the contract year, when nothing is left to trade.

Everything that is not ocean freight. A volume agreement almost never covers inland haulage, destination terminal handling or the forwarder's documentation fees, and on a US import those items plus the customs bond can rival the ocean leg — see our guide to importing into the United States. Comparing two contracts on the ocean rate alone is comparing two cars on the price of a tank of fuel.

The honest way to decide is to put both structures into one full landed-cost model, on your real volume, under both market scenarios. The TRADE-COST calculator lines up freight, surcharges, duty and tax so the rate gap converts into dollars per unit sold — the only unit in which the decision is really made, and usually the one that shows the negotiation was fought over the wrong variable.