Sea freight vs air freight: Choosing the right shipping mode for your order
Cost per kg, lead time, break-even points and which mode wins for which product. Plus how to think about LCL vs FCL containers.
Sea freight basics
Container vessels carry roughly 90% of global goods by volume — including most of what BestDealz Class B handles. Cost per kg is the lowest of any transport mode, but transit is slow: typically 18–25 days port-to-port from China to South Africa.
Routes
- Shanghai → Durban — most common, ~22 days
- Shenzhen → Cape Town — ~24 days, often via transshipment
- Ningbo → Port Elizabeth — less common, ~25 days
LCL vs FCL
Two ways to buy sea freight:
LCL (Less than Container Load)
You pay per cubic metre. Your goods share a container with other shippers' cargo. Best for orders 1–15 m³.
- Typical cost: USD 70–110 per m³ to Durban
- Extra handling time at both ports (consolidation/deconsolidation)
- Best for first-time orders, samples, mid-volume
FCL (Full Container Load)
You book and pay for the whole container.
- 20-ft container — ~28 m³ capacity, ~USD 1,200–1,800 to Durban
- 40-ft container — ~58 m³, ~USD 1,800–2,800 to Durban
- 40-ft HC (high-cube) — ~66 m³, slight premium for the extra foot of height
Air freight basics
Charged per kg or per volumetric kg (whichever is higher). Volumetric kg = (L × W × H in cm) / 6000.
Cost
- Typical USD 4–7 per kg China → SA airport
- Add USD 0.50–1.50/kg for customs + last-mile
- Lead time: 5–7 days door-to-door
When it makes sense
- Sample orders (always)
- High-value, low-weight items (electronics, jewellery)
- Urgency overrides cost (replacement parts, time-critical launch)
- Small parcels under 30 kg total
Cost comparison
| Mode | Cost per kg | Lead time | Best for |
|---|---|---|---|
| Sea LCL | USD 0.50–1.20 | 30–40 days door-to-door | 1–15 m³ |
| Sea FCL 40-ft | USD 0.30–0.50 | 30–40 days door-to-door | 15+ m³ |
| Air freight | USD 4–7 | 5–7 days door-to-door | < 200 kg, urgency |
| Express (DHL/UPS) | USD 8–15 | 3–4 days | Samples, < 30 kg |
The break-even calculation
To decide sea vs air, compare total landed cost — not just freight. A simple formula:
If (air freight cost − sea freight cost) < (holding cost over the extra time), fly it.
Worked example: 80 kg of electronics, FOB value USD 6,400. Air = USD 480 + 5 days. Sea LCL = USD 95 + 32 days. Difference is USD 385 to save 27 days. If you can resell in those 27 days for >USD 385 margin, fly it. Otherwise, sea wins.
What BestDealz uses by default
For Class B orders:
- < 50 kg or < 0.4 m³ — air freight included (5–7 day lead)
- 50–500 kg — sea LCL (30–35 day door-to-door)
- > 500 kg or > 15 m³ — sea FCL (28–32 day door-to-door)
You can override the default at checkout — pay extra to upgrade an LCL order to air, or downgrade an air order to sea for a 30% discount. For repeat customers, we also offer monthly consolidation FCLs to lock in the lowest possible rate.
Want us to source this for you?
Submit an RFQ — our sourcing team will return 3 supplier quotes within 24 business hours, all-in landed price.
Submit RFQ →