Why does peak season exist in shipping?

Global shipping demand is not the same all year round. It follows predictable patterns driven by consumer behaviour, retail calendars, and manufacturing cycles — especially in Asia, which produces a large share of the world's goods.

Certain times of the year see a massive rush of cargo hitting the ports all at once. Ships get fully booked weeks in advance. Space becomes scarce. And when space is scarce, rates go up.

Think of it this way: Imagine trying to book a flight home during Diwali or Christmas week. Prices are 2x or 3x normal, seats fill up fast, and you either pay the premium or travel at an inconvenient time. PSS is the shipping equivalent of that festive season flight surcharge — demand spikes, prices follow.

When does peak season happen?

There are two major peak seasons in ocean freight every year:

Pre-Golden Week / Pre-Chinese New Year (January–February) Chinese factories shut down for 2–4 weeks during Chinese New Year. To avoid running out of stock, importers rush to move cargo before factories close. This creates a surge in demand in the weeks leading up to the holiday, typically January to early February.

Pre-Holiday / Back-to-School Season (July–October) This is the biggest peak season. Retailers in the US and Europe need their shelves stocked for back-to-school shopping (August), Halloween (October), Black Friday (November), and Christmas (December). Since ocean freight takes 3–6 weeks, cargo must leave Asia between July and October to arrive in time. This causes a massive rush of bookings on Asia–US and Asia–Europe trade lanes.

Outside these two main windows, smaller regional peaks can occur around local holidays, sporting events, or sudden demand spikes (like pandemic-era demand surges).

How much is PSS and how is it charged?

PSS is charged as a fixed amount per container — per TEU (20ft) or per FEU (40ft). The amount varies by carrier, trade lane, and how intense the demand surge is.

Typical PSS range: $200 to $800 per TEU during moderate peaks. During extreme demand surges (like 2020–2021), PSS and combined surcharges went far beyond this.

Example — 1 x 40ft container (FEU), Asia to US West Coast, during peak season:

• Base ocean freight rate: $1,500

• BAF (Bunker Adjustment Factor): +$320

• CAF (Currency Adjustment Factor): +$75

• PSS (Peak Season Surcharge): +$500

• Total freight cost: $2,395

Without PSS the same shipment would cost $1,895. The peak season alone adds $500 per container.

How far in advance is PSS announced?

Shipping lines typically announce PSS 30 days before it takes effect — similar to GRI. The announcement will specify:

• The effective start date

• The end date (or "until further notice")

• The amount per TEU/FEU

• Which trade lanes it applies to

Unlike GRI, PSS has a defined end date (or an expected removal window), because it's tied to a seasonal demand window — not a permanent rate change.

Does PSS always get fully implemented?

Not always. Just like GRI, PSS is an announcement. Whether carriers can enforce the full amount depends on how tight vessel capacity actually is:

If vessels are fully booked and space is genuinely scarce, carriers enforce the full PSS with no negotiation room.

If there is more capacity than expected or demand is softer than predicted, shippers and forwarders can negotiate a lower effective rate — or PSS may not be enforced at all.

The key variable is vessel utilisation — how full the ships actually are. When ships are 95%+ full, PSS sticks. When ships are running at 70–75% capacity, PSS becomes more flexible.

PSS vs. GRI vs. EBS — what's the difference?

PSS (Peak Season Surcharge) — Temporary. Tied to a specific demand season. Added on top of base rate. Removed after peak period ends.

GRI (General Rate Increase) — Permanent change to the base rate itself. Not seasonal. Driven by profitability needs, not demand cycles.

EBS (Emergency Bunker Surcharge) — Temporary fuel-related surcharge triggered by a sudden oil price spike. Not seasonal — triggered by commodity market events.

The simplest way to remember it: PSS is about demand. GRI is about profitability. EBS is about fuel emergencies.

Why does PSS matter to you as a shipper?

It can significantly increase your shipment cost with just 30 days notice. A $400–$600 PSS on a 10-container order adds $4,000–$6,000 to your freight bill overnight.

Timing your shipments around peak season saves real money. Shipping 4–6 weeks before the peak window begins lets you move cargo at normal rates before PSS kicks in.

Space gets scarce, not just expensive. During peak season it is not just about cost — vessels get fully booked. If you don't book early, you may not find space at any price and your shipment gets rolled to the next vessel, causing delays.

Retailers and seasonal businesses are most exposed. If your business has a hard deadline — like getting stock on shelves before Christmas — you have very little leverage to avoid PSS. Planning ahead is your only real protection.

How to reduce the impact of PSS on your business

Ship early. Book your cargo 6–8 weeks before peak season begins. You get pre-peak rates, better vessel space availability, and more flexibility if there are delays.

Use a service contract. If you ship regularly, a long-term contract with a carrier or forwarder may lock in rates that exclude or cap PSS during peak periods.

Consider alternative routings. During Asia–US West Coast peak surges, routing via the East Coast or through alternative transshipment hubs sometimes offers better rates.

Split shipments strategically. If you have flexibility, ship part of your order before the peak and the remainder after it ends.

Work with a good freight forwarder. They will flag upcoming PSS announcements and help you decide whether to accelerate, delay, or reroute your shipment to minimise cost.

Conclusion

• PSS is a temporary surcharge — it is added and removed seasonally

• Charged per TEU or FEU on top of the base freight rate

• Two main peak seasons: January–February (pre-CNY) and July–October (pre-holiday)

• Typically announced 30 days before the effective date

• Amount ranges widely — $200 to $800+ per TEU depending on trade lane and demand intensity

• Does not change the base rate — unlike GRI