The simple rule
The decision between air and sea freight comes down to two questions, in this order:
- Can your business afford to wait 45–55 working days for the goods? If yes, sea freight. If no, air freight.
- Is the shipment under 1 CBM? If yes, the sea-freight 1-CBM minimum means air may be competitive even if you can afford to wait. Compare both.
That's it. Cost is rarely the deciding factor — sea freight is 5–13× cheaper per kilogram than air on almost any commercial shipment. The real question is whether the speed premium is worth the cash. For most South African importers, the answer is "send everything by sea except urgent stock, samples, and small shipments under 1 CBM."
Side-by-side comparison
- Speed: 45–55 working days door-to-door
- Charged on: CBM or chargeable weight (1 CBM = 1000 kg)
- Best for: 1 CBM+, non-urgent, bulky/heavy goods
- Ports: Durban, Cape Town
- Effective rate: ~$1–$1.50/kg on typical loads
- Watch out for: long lead time, can't recover days lost
- Speed: 7–10 working days door-to-door
- Charged on: chargeable kg (greater of actual or volumetric)
- Best for: urgent, small (<200 kg), high-value goods
- Airports: OR Tambo, Cape Town, King Shaka
- Effective rate: $13/kg + surcharges
- Watch out for: volumetric weight, surcharges, small-order fees
Rates above are indicative 2026 starting prices. Freight rates fluctuate — always confirm a live rate before committing to a supplier. See our live freight calculator for both modes.
Three worked examples
To make this concrete, here's the same product shipped at three different volumes — assuming general goods (no surcharges) and a typical density of 250 kg per CBM.
Example A: small order — 0.4 CBM, 100 kg
| Mode | Calculation | Cost (USD) |
|---|---|---|
| Sea (1 CBM min) | 1 CBM × $305 | $305 |
| Air | 100 kg × $13 | $1,300 |
| Winner on cost | Sea is ~4× cheaper | Sea $305 |
For a 0.4 CBM shipment, the sea-freight minimum means you pay for a full CBM even though you only fill part of it. It's still cheaper than air. If you can wait.
Example B: medium order — 2 CBM, 500 kg
| Mode | Calculation | Cost (USD) |
|---|---|---|
| Sea | 2 CBM × $305 | $610 |
| Air | 500 kg × $13 | $6,500 |
| Winner on cost | Sea is ~11× cheaper | Sea $610 |
At 2 CBM, sea is the obvious choice. You'd pay $5,890 more to get the goods 6 weeks sooner — only worth it for a genuine emergency.
Example C: large order — 15 CBM, 4,000 kg
| Mode | Calculation | Cost (USD) |
|---|---|---|
| Sea | 15 CBM × $305 | $4,575 |
| Air | 4,000 kg × tiered rate (~$4–$5/kg at this weight) | ~$18,000 |
| Winner on cost | Sea is ~4× cheaper | Sea $4,575 |
For container-scale orders, air freight tiered rates drop significantly, but sea still wins by 4× or more. Air at this scale is only used for genuine emergencies — a missed launch, urgent spares for a production line, etc.
Transit time breakdown
| Stage | Sea Freight | Air Freight |
|---|---|---|
| Production lead time (from order) | 15–30 days | 15–30 days |
| China export customs & loading | 2–3 days | 1–2 days |
| International transit | 28–35 days | 1–2 days |
| SA customs clearance | 5–10 days | 2–4 days |
| Local delivery to your door | 1–3 days | 1–2 days |
| Total from order to door | 50–80 days | 20–40 days |
Production lead time is the same regardless of how you ship — you can't accelerate the factory by booking air freight. If your supplier quotes 30 days production, the earliest air-freight delivery date is still ~40 days from order confirmation. The decision lever is the international transit + SA customs stages, which is where air saves you 4–6 weeks.
When to choose sea freight
Sea freight is the right answer when:
- Your order is 1 CBM or larger (almost always)
- You have more than 8 weeks between order and need-by-date
- The goods are bulky or heavy relative to value (kitchenware, machinery, hardware, building materials)
- You're stocking regular replenishment — not racing a launch
- Freight cost is a meaningful percentage of your margin
When to choose air freight
Air freight is worth the premium when:
- The shipment is under 1 CBM and you're sea-freight-minimum-constrained
- You need the goods within 4 weeks of order for a launch, event or deadline
- The goods are small, dense and high-value (electronics, jewelry, specialist parts) — freight is a smaller % of cost
- You've sold the stock already and cash flow penalty of being out of stock exceeds the freight premium
- It's a first batch of new stock while bulk follows by sea (see split shipment below)
- Samples or replacement parts — speed matters, weight is low
The hybrid option: split shipment
One under-used strategy: ship the first 50–200 units by air to start selling immediately, then ship the bulk of the order by sea 5–6 weeks later. You pay an air-freight premium on a small batch only, while keeping the majority of your goods on cheap sea freight.
This works exceptionally well for:
- E-commerce product launches where you need to start fulfilling pre-orders
- Seasonal stock where missing the first 4–6 weeks costs more than the air premium
- New product lines where you want to validate demand before the bulk lands
- Replacement of stock-out items mid-cycle
Storm media handles split shipments on the same purchase order — both batches go through one quote, one customs entry per shipment, one delivery.
For a full breakdown of the import process and how freight fits in, see our step-by-step guide to importing from China to South Africa. For the tax side — what you'll pay SARS on either freight mode — see our guide to import duties and taxes.