How ShipGenius Rates Work

When you rate a shipment, ShipGenius asks every carrier account you have access to at the same time and brings back every service that will take the package, each with a price and a delivery estimate. There's no default carrier and no favorite. What you see is the full picture of what that package costs today.

Below, we'll walk through what goes into those numbers, why the winner changes from package to package, and how to read a rate list well enough to spot when something looks off.

What Gets Rated

Every time you rate, we reach out to every carrier account your shipper account can use. That includes ShipGenius carrier accounts on Core and Plus, plus any of your own accounts you've connected. If you have several accounts with the same carrier, we'll check them all.

Each carrier decides which of its services are a fit for your package. A service drops off the list when the carrier turns the package down: too heavy, outside its size limits, not delivered to that address, or restricted because of what's inside. We show you those reasons right alongside the rates, so if the list looks shorter than you expected, the explanation is usually sitting right there.

What Moves the Price

Billable Weight

Carriers bill on whichever is greater: actual weight or dimensional weight. Dimensional weight is length times width times height divided by a carrier-specific divisor, so a big, light box gets billed as though it were heavy. It's the most common reason a rate comes back higher than a shipper expected.

That's why length, width, and height are required alongside weight. ShipGenius won't rate a package without them. Entering the real box size takes a moment up front, and it's what keeps the price you see from turning into a billing correction after the label is bought.

Zone

Zone is the distance band between where a package starts and where it's going, worked out from the two ZIP codes. Higher zones cost more on nearly every service. That's why changing your ship-from address changes every price in the list, and why shipping from a second warehouse can give you a noticeably different set of rates.

Surcharges

Carriers add accessorial charges on top of their base rates, and no two of them handle those charges quite the same way. The ones you'll run into most:

• Residential delivery: most carriers charge more to deliver to a home than to a business. Address validation is what determines residential status, so validating before you buy really does pay off.
• Fuel surcharge: a percentage of the base rate that carriers reset from time to time. Two carriers with the same base rate can end up meaningfully apart once fuel is added.
• Delivery area surcharge: extra for rural or extended delivery areas.
• Oversize and additional handling: added when a package goes past the size or shape limits, which vary by carrier.

Your Rate Card

On Core, you ship on ShipGenius negotiated rates, which come in better than retail pricing. On Plus with your own carrier accounts, you ship on the rates you've negotiated yourself. When both are available, they show up side by side so you can compare them.

Why the Cheapest Carrier Keeps Changing

No single carrier is cheapest across the board. Here's the pattern most shippers notice over time:

• USPS Ground Advantage usually wins on light parcels, especially under a pound and going to a home.
• UPS and FedEx ground usually win on heavier parcels and business addresses, where their residential surcharges don't apply.
• UPS SurePost and similar hybrid services win in a narrow band: heavy enough that USPS retail pricing starts to hurt, light enough that full ground is more than you need.
• Zone flips the outcome. A carrier that wins at zone 2 often loses at zone 8.

That's why it's worth rate shopping every shipment instead of picking one carrier and sticking with it. The difference on a single label is usually small, but across a few thousand labels it adds up.

Reading the Rate List

Each rate shows you the carrier, the service, the price, and an estimated delivery. Those estimates come from the carrier rather than from us, and how binding they are varies: express services usually carry a guarantee, ground services usually don't.

Details from the carrier such as zone and billing weight come back with each rate. If a price looks off, billing weight is the first thing to check: when it's higher than the weight you entered, dimensional weight is being applied.

Narrowing the List with Rate Groups

A long rate list is great when you're exploring your options and slower than you'd like in a busy warehouse. Rate groups let you save a named set of carrier services (your ground, two-day or international options) and rate against just that set.

That's faster, and it also keeps someone from accidentally picking an expensive express service on an order that only needed ground. See Rate Groups for how to configure them.

Rate and Ship in One Step

If a rule already makes the shipping decision for you, like cheapest ground, fastest under a price ceiling or a set carrier for a product, nobody needs to look at a rate list.

The API can rate and ship in a single call: you send the shipment along with a service specification, using filters such as maximum delivery time, carrier priority, or service group, and it rates, picks, and creates the label for you. On OMS, workflows do the same thing inside the product without any code. See The Workflow System.

The Retail Convenience Fee

Core accounts pay a small per-batch convenience fee on top of the carrier total at checkout. It's worked out from the batch total and shown before you confirm, so the number you approve is the number you pay. Plus and above don't pay it. Instead, labels on your own carrier accounts carry a ShipGenius fee per label. For new accounts, the first 2,500 BYO labels are free. Then it's 2¢ a label for your first 6 months, and 7¢ falling to 2¢ as your monthly volume grows.

FAQs

Why did my rate change between rating and buying?

Rates come straight from the carrier every time you rate. We don't save or reuse an earlier rate request. If anything that feeds the price changes, such as the address, weight, dimensions, extra services, or residential status, rate again and you'll see the current price. Carriers also update fuel surcharges on their own schedule.

Why is a carrier missing from my rate list?

A few things can cause it: there's no account connected for that carrier, the account is turned off, its connection test is failing, a rate group is filtering it out, or the carrier turned the package down. We show rate errors right next to the results, so that's the first place to look.

The carrier billed me more than the rate I bought.

It's almost always billable weight. Carriers re-measure and re-weigh packages as they move through their network, and if the real dimensions are bigger than what you entered, they bill the difference as an adjustment. Accurate dimensions clear up nearly all of these. If one still looks wrong, get in touch and we'll take a look.

Do delivery estimates come with a guarantee?

It depends on the service. Express services generally come with a delivery commitment; ground services generally give you an estimate with no guarantee attached. Either way, the estimate you see is the carrier's own, passed through unchanged.

Can I rate without buying?

Absolutely. Rating is free and unlimited, so run rates as often as you like and buy only when you're ready. Identity verification isn't part of rating, and most accounts never run into it at all.

Do I need dimensions to get a rate?

Yes. Length, width, and height are required alongside weight, so every rate is built from the real size of your package. That's what keeps the price you see in line with what the carrier bills you later.

How does ShipGenius pick which rate is cheapest?

We don't pick for you. The full list comes back, and the choice is yours. Automatic selection happens only when you ask for it, through the API's rate-and-ship service specification or an OMS workflow.