Carrier fuel surcharges are rising: what AU retailers need to do now to protect margins

2026-03-19

Written by Kimberley Hughes

Shipping costs are rising again, but not in a way most retailers notice until the damage is already done.

Shipping fuel surcharges are quietly increasing globally due to the rising tension in the Middle East. Because they’re applied as percentages and often lag behind real fuel prices, they don’t hit all at once. They show up gradually, across invoices, over weeks.

That’s what makes them dangerous. You could be losing margin on every order without a clear signal. Your shipping rates stay the same, your checkout looks stable... but your underlying costs keep climbing.

Global fuel markets have become more volatile, and carriers are already adjusting their surcharge tables in response. Because of how those surcharges are calculated and applied, the full impact is still working its way through the system. What you’re seeing today may not be the peak.

For retailers, this creates a simple but critical problem: your shipping costs are no longer predictable, but your pricing often is. If your setup can’t adapt, your margins take the hit.

In this guide, we’ll break down what’s driving these changes, how fuel surcharges actually work, and what you can do now to stay in control before costs move further.

What’s driving fuel costs up right now?

Tensions in the Middle East have put pressure on one of the world’s most important oil routes, the Strait of Hormuz. Around 20% of global petroleum supply passes through that corridor, and there are very few viable alternatives if it becomes disrupted. Even the possibility of disruption is enough to push prices up.

We’re already seeing the real-world impact:

  • In New Zealand, petrol prices rose roughly 50 cents per litre over March, reaching just over $3 on average.
  • In Australia, prices jumped nearly 49 cents per litre within a few weeks.
  • Airlines like Air New Zealand have reduced flights due to rising jet fuel costs, showing how quickly fuel impacts capacity and pricing.

Every part of the delivery network depends on fuel. When fuel becomes more expensive, transport becomes more expensive. And carriers don’t absorb that cost, they pass it on.

But they don’t always do it in a way that’s obvious.

The hidden costs: how to calculate fuel surcharges

Fuel surcharges are typically calculated with three common characteristics:

1. They are index-based

Carriers commonly reference external indices such as US Gulf Coast jet fuel and diesel indices (or national diesel averages), then map those to a percentage surcharge table. DHL’s published methodology for its air fuel surcharge references the US Gulf Coast jet fuel spot price and shows the surcharge chosen from a step table.

2. They are applied as a percentage on charges, not a fixed dollar amount

NZ Post explicitly explains that its “Variable Price” component is calculated as a percentage of the applicable Base Price and is comprised of Variable Fuel Rate (VFR), Road User Charge (RUC), and sometimes Temporary Continuity Cost (TCC). It also provides a formula:

Base Price + (Base Price × (VFR% + RUC% + TCC%)) = Total Price (excl. GST).

This is exactly why flat-rate checkout pricing can break – even if the base transport charge stays stable, the variable components can move.

3. They often have lags and different update timing

This creates the “calm before the storm” effect, but it varies by carrier:

  • TNT’s APAC fuel surcharge page explicitly states there will be a two-week lag between the fuel price index and the applied surcharge, and that changes are effective each Monday.
  • FedEx’s fuel surcharge page notes a lag between the fuel price index and the fuel surcharge, and that FedEx may use a longer lag when index publication is delayed.
  • Aramex’s US fuel surcharge explanation includes a two-month lag example: June monthly average used to determine August surcharge.
  • NZ Couriers states fuel surcharges are applied and effective on the first Monday of each month (unless changed after that) and indicates information is usually available about one week before it is applicable.

There is often a lag (anywhere from ~2 weeks to ~2 months depending on carrier and service), so a fuel spike today can show up on invoices progressively over the next 6–8 weeks.

💡 If surcharges are eating into your margins, your fulfilment efficiency matters even more.

Try our Cost Savings Calculator to see how much you can save with automation.

Calculate my savings

March snapshot: Current carrier fuel surcharges for retailers

To understand how this plays out in practice, it’s worth looking at where fuel surcharges are sitting right now. Across New Zealand and Australia, domestic courier surcharges are already at levels that can meaningfully impact margins. As of April 2026, NZ Post’s courier variable rate sits at a combined 3.50%, made up of fuel and road user charges. NZ Couriers is higher at 7.80% domestically, while the Australia Post surcharge is at 4.8% and Aramex Australia at 6.70%, based on national diesel pricing and their own operating costs.

Some carriers are moving more drastically. TNT (FedEx) domestic services in Australia are sitting at 21.5% for the period from late March through early May, reflecting fuel movements over a rolling three-month window.

Once you move into international and express services , the percentages increase significantly. DHL Express and NZ Couriers international services are both at 30.50% for March 2026, while FedEx and UPS export rates are sitting in the low 30% range, with import rates pushing into the mid-30s. In some regions, FedEx tables are already showing international surcharges as high as 40%, depending on the lane.

CarrierLane contextPublished surchargeDate/period shown
NZ PostDomestic courier variable pricingVFR 2.90% + RUC 0.60% (= 3.50%)April 2026
NZ CouriersDomestic7.80%April 2026
Australia PostDomestic/business shipping4.8%April 2026
Aramex AUDomestic6.70%April 2026
TNT Domestic AUDomestic21.5%29 Mar–2 May 2026
DHL ExpressInternational air30.50%March 2026
NZ Couriers Intl ExpressInternational air30.50%March 2026
FedEx (indicator)International express (US table)Export 30.75%; Import 34.50%Week starting 16 Mar 2026
UPS (indicator)International air (US indicator)Export 30.75%; Import 34.5%Week starting 16 Mar 2026

Disclaimer: fuel surcharges vary by service, lane, and contract, and may apply differently to base transport charges and accessorials. Carrier tables can change without notice.

The key point here isn’t just the percentage itself, but how widely it varies. Domestic services might sit in single digits, while international air shipments can carry surcharges that are ten times higher.

That gap matters when you’re setting up shipping pricing, especially if you’re using a single approach across both domestic and international orders.

Starshipit tip: When surcharge levels vary this much between carriers, relying on a single provider increases your exposure to cost swings. A multi-carrier setup gives you options. With Starshipit, you can compare rates across carriers and automatically select the most cost-effective option for each order, helping you manage these differences without adding manual work.

What this does to your margins (and why it’s happening now)

The reason fuel surcharges catch retailers off guard isn’t just that they increase costs. It’s how they’re applied.

Most carriers calculate fuel surcharges as a percentage of the base transport cost. In some cases, that percentage is made up of multiple components, such as fuel rates, road user charges, and other temporary adjustments. That structure creates a compounding effect. The surcharge isn’t a flat fee added once. It scales with the underlying cost of the shipment, and in some cases, multiple variable components can stack on top of each other.

Carriers are also designed to pass these changes through quickly. For example, some explicitly separate fuel and related charges from fixed pricing so they can adjust them up or down as conditions change. In periods of disruption, additional fees can also be layered in. Industry reporting has already pointed to conflict-related surcharges being applied to certain lanes, adding another layer on top of standard fuel adjustments.

When you put all of that together, the impact on retail margins becomes clearer.

Real-world example of how fuel surcharges quickly impact margins

If you charge a flat $9 for domestic shipping and your underlying carrier cost averages $8.40 , you’re left with a $0.60 margin before any fulfilment costs are factored in.

Now introduce a 5 percentage point increase in variable surcharges. Applied to that $8.40 base, that’s an additional $0.42 per shipment . Your margin drops from $0.60 to $0.18 almost immediately.

At that point, it doesn’t take much more movement for shipping to become a loss.

A slightly higher-cost zone, a heavier parcel, or another surcharge adjustment can tip the balance entirely . And because these changes are incremental, they often go unnoticed until they’ve already had an impact across a large number of orders.

Starshipit tip:This is where static shipping pricing starts to break down. If you’re relying on flat rates or fixed thresholds, small percentage changes can quietly erode your margin. Using live carrier rates at checkout helps you stay aligned with real costs as they change, rather than absorbing those increases over time.

Why the next 6-8 weeks are crucial for shipping costs

What makes the current situation more challenging is timing. Fuel prices have already moved sharply over March. Those price changes are the input carriers use to calculate their surcharge tables.

But because most carriers use lagged indices, those increases don’t show up all at once. Some apply changes with a short delay of a couple of weeks. Others use monthly updates. In some cases, there can be a lag of up to two months between fuel price movements and the surcharge applied to shipments.

This means the impact is spread out over time. Even if current published surcharge rates still look relatively stable, they may not yet reflect the full extent of recent fuel price increases. As those updates roll through, costs can continue rising across multiple billing cycles.

Industry reporting is already pointing to ongoing volatility, not just in fuel surcharge tables, but also in additional fees tied to affected regions and routes. For retailers, the takeaway is simple: what you’re seeing now may not be the peak.

Starshipit tip: When costs are moving with this kind of lag, reacting after the fact is too late. Setting up automation rules to select the most cost-effective carrier for each order helps you respond as conditions change , without needing to constantly monitor and adjust manually.

Ways to manage rising fuel surcharges right now

At this point, the goal isn’t to perfectly predict fuel surcharges. It’s to make sure your shipping setup can absorb change without constantly needing to be rebuilt.

For most retailers, that means focusing on a few practical adjustments that protect margins without adding operational complexity.

1. Start with your pricing structure

The first step is to rethink how your shipping pricing holds up under variability.

There are two things you’re trying to balance here. On one side, you need to protect profitability as costs move. On the other, you need to keep the checkout experience simple enough that it doesn’t hurt conversion.

In practice, that usually means avoiding constant price changes and instead adjusting the structure around them.

A common approach is to keep a stable, easy-to-understand domestic offer, but build a buffer into your margin to account for fuel volatility. From there, you can use service tiers more strategically , showing premium or express options only when they make sense, such as for higher-value or time-sensitive orders.

The data we’re seeing now shows just how wide the range can be. If your pricing model assumes the lower end of the range, it doesn’t take much movement to create pressure.

Starshipit tip:This is another area where live rates at checkout and shipping automation rules become useful. Live rates at checkout show your customers the real-time cost from your carriers, based on the cart’s weight, dimensions and destination. Combined with automation rules, you can protect your margins by adding a flat fee or percentage to the quoted rate before it’s shown at checkout.

So, if a carrier fuel surcharge (or other surcharge) isn’t always included in the live quote, you can set a rule to automatically add a buffer when it’s likely to apply (for example, when order weight is over a threshold). This way you’re not caught out by unexpected surcharges, and you keep control over your shipping profitability.

2. Run a quick “what if” scenario

You don’t need a complex model to understand your exposure.

A simple way to get clarity is to take a recent period, such as your February shipment data, and apply a small increase to fuel-related components . Even a +5 to +10 percentage point adjustment across affected lanes is enough to highlight where things start to break.

Recent fuel price movements show how quickly those inputs can shift, and those changes are still flowing through carrier surcharge tables. The goal here isn’t to predict exactly what will happen; it’s to identify your weak points.

In most cases, the pressure shows up first in specific areas. Heavier parcels, rural deliveries, and international express shipments tend to be the most sensitive to percentage-based increases.

Once you know where those pressure points are, you can decide how to handle them before they scale.

Starshipit tip: With shipping analytics and reporting, you can quickly break down your orders by cost drivers like zone, weight, and service level. That makes it easier to spot where margin is being squeezed and adjust your setup accordingly.

3. Focus on reducing the base cost

One of the more overlooked ways to manage fuel surcharges is to reduce the shipping cost they’re applied to in the first place.

Because surcharges are percentage-based, any reduction in your base shipping cost also reduces the dollar value of the surcharge.

That’s where packaging and fulfilment decisions become more important than most retailers realise.

Too often, products are shipped in boxes that are simply too large. In a busy warehouse environment, teams prioritise speed over optimisation , grabbing the nearest available package rather than the most efficient one. It’s understandable, but it comes at a cost. Larger boxes increase both actual and volumetric weight, pushing shipments into higher pricing brackets and inflating surcharges.

At the same time, failing to consolidate orders means you’re paying surcharges multiple times when you don’t need to. Merging shipments where possible reduces the number of parcels moving through your network, lowering both base costs and the total surcharge applied.

Getting this right doesn’t require a complete operational overhaul. Standardising carton sizes, guiding pick-and-pack teams toward better choices, and consolidating orders can significantly reduce shipping costs at scale. Even small improvements compound quickly when applied across every order.

These aren’t new ideas, but in a percentage-based cost environment, they become more valuable.

Starshipit tip: Features like Recommended Packaging help warehouse teams choose the right package every time, while shipment consolidation and Address Validation reduce unnecessary costs and delivery issues. The result is a lower base shipping cost and a smaller surcharge applied to every order.

The takeaway: stay in control as shipping costs move

Fuel surcharges aren’t new, but the way they’re moving right now is. What used to be a relatively stable cost sitting quietly in the background is now shifting more frequently, and in ways that are harder to predict. The impact isn’t always obvious straight away, but it builds over time as small percentage changes compound across every shipment.

That’s what makes this moment different. It’s not just about higher costs, it’s about variability.

The retailers that handle this well aren’t constantly reacting to every update. Instead, they’ve built flexibility into their setup. They understand where their margins are most exposed, they’ve structured their pricing to absorb movement, and they’re using automation to make decisions at scale.

If there’s one thing to take away from the current environment, it’s this: assume your shipping costs will keep changing, and plan for that upfront to stay in control. The retailers who do will protect their margins without sacrificing the customer experience.

If your shipping setup can’t adapt to changing costs, your margins will take the hit.

Starshipit helps you stay ahead with automated carrier selection, live rates, and full visibility into your costs.

If you’re ready to see Starshipit in action, start your 30-day free trial now or book a custom demo with our team of shipping experts.

Kimberley Hughes

Kimberley Hughes

Kimberley is Starshipit's Content Marketing Lead. Her days are filled with creative storytelling and innovative content strategies. Off the clock, she's an all-seasons iced coffee fan, a Catan strategist, and skincare explorer. For a peek into her world, find her on LinkedIn.

More from this Author

Read our related articles

2022-09-23
Peak season shipping

2022 Holiday shipping deadlines