Multi-carrier shipping software: every carrier account on one screen

Sellers rarely run on one carrier account. You add a UPS account for a promo rate, a retailer hands you its FedEx account for drop-ship orders, and Amazon wants Buy Shipping. Rilk keeps every one of those accounts on one screen. It bills the retailer when the order is the retailer's and picks the cheapest rate that still arrives on time.

Can I use more than one UPS or FedEx account?

Yes. Connect as many UPS and FedEx accounts as you have, and every rate shows which account it comes from. Sellers end up with several accounts for ordinary reasons. A carrier offers better rates two years in, but only on a new account number under the same login. Or a retailer you drop-ship for wants its orders on its own account.

Rilk compares all of them together, each as its own line with the account name on it. A 2-day order can show FedEx 2Day on your main account, FedEx 2Day on the promo account, FedEx 2Day One Rate, UPS 2nd Day Air on your own account, and, on a Walmart order, Walmart's own 2-day label. Each line has its price and delivery estimate, so you see which account is cheapest on this order, not on average.

Ship a retailer's drop-ship orders on the retailer's account

When a retailer pays the shipping, it gives you its UPS or FedEx account number. Sometimes the label must be billed third party; sometimes it does not. In Rilk you enter the retailer's account number once, per marketplace. You do not need the retailer's login: for UPS it takes the account number and postal code; for FedEx, the account number. You also pick which of your own accounts makes the label. That matters because the retailer has usually approved one specific account of yours to ship on its account. From then on every order from that retailer is billed to the retailer automatically, while your eBay and Amazon orders keep shipping on your own rates.

We ran this on desktop shipping software for years. Using a second account for third-party billing meant saving a profile, closing the program, re-importing the profile and running another copy with different credentials. In Rilk it is a setting in the browser.

Third-party billing on UPS and FedEx labels
Add the retailer's account with the account number, no login
Set once per marketplace; every order from that channel follows it
Choose which of your own accounts generates the third-party label

Use your own negotiated carrier rates

Connect your own UPS, FedEx, USPS and DHL Express accounts and your negotiated rates are the rates you see. Rilk adds nothing to them. FedEx accounts register inside Rilk: enter the account and confirm the PIN. FedEx One Rate is supported.

Get the cheapest label that still arrives on time

Rilk waits until every connected carrier has answered, so a slow carrier can never push you onto the second-cheapest rate. It drops every rate that would land after the marketplace's delivery date, then buys the cheapest of what is left. When two rates cost the same, it takes the one that arrives sooner. If no rate can arrive on time, it stops and flags the order. It never quietly falls back to a late service, because a late delivery costs more than the label saved. The label cost lands on the order and in your profit the moment you buy it.

Amazon Buy Shipping: every Amazon order, every time

On Amazon, buying the label through Amazon Buy Shipping is about protection more than price. In Amazon's words, "With Amazon Buy Shipping, we refund costs for claims when customers report that packages don't arrive", and that protection depends on buying the label through Buy Shipping. In our experience it works like signature confirmation on every label, and signature alone is sometimes not enough to win a claim. Price is not the trade-off either, because Amazon lets you link your own UPS or FedEx account to Buy Shipping and keep your negotiated rates.

Turn on "Buy Shipping only" in Rilk and every Amazon order ships on Amazon Buy Shipping. The automatic pick, bulk shipping and the rate screen offer nothing else. Leave it off and the Buy Shipping rate sits next to your own carrier rates, and you choose.

Walmart Buy Shipping next to your own rates

Walmart works differently, so Rilk treats it differently. Whether Walmart's label is the cheaper one depends on your shipping template. On 2- and 3-day services Walmart subsidises its sellers' labels, and UPS's express services and FedEx 2Day One Rate on Walmart's label often come in well under your own rates. On a next-day template there is no subsidised Walmart rate, and you ship on your own account. A Walmart-only rule would leave those orders with nothing to buy. So Rilk shows Walmart's rates and yours together, and you buy whichever is cheapest. If you do set Walmart only, orders with no Walmart rate fall back to your own carriers.

It used to be worse. When UPS was missing from Walmart's API, sellers who wanted that saving bought the label on the Walmart portal. Then they went back to their shipping tool to mark the order shipped by hand. Walmart has since opened that up, and in Rilk both labels come straight through the API on the order. Tracking goes back to Walmart by itself.

Label reference fields set per marketplace

Every retailer wants something different in the reference fields on the label. One wants its PO number, another wants the SKU and quantity, and a third wants your own order number. Get it wrong and the retailer cannot match the box to its order. In Rilk you decide what goes in each reference field, per marketplace, with a default for everything else. You set it once, and every label for that channel follows it.

A retailer template can read Ref 1 = the channel PO (PO1234) and Ref 2 = quantity and SKU per line (1X SKU-A, 2X SKU-B). Rilk fits that into each carrier's own limits: 2 reference lines of 35 characters on UPS, 3 lines of 40 on FedEx, 1 on DHL eCommerce. Where a retailer mandates its own references, Rilk fills them for you: Zoro's FedEx PO, customer reference and invoice number go on every Zoro label, and Home Depot's UPS references go on its labels by default, with no setting needed.

Three reference fields per marketplace, plus an "all marketplaces" default
Fill them with the channel PO, the Rilk order number, SKUs, quantity and SKU per line, your own SKU, order notes, package type or the marketplace name
Each carrier's line count and character limit is handled for you
Retailer-mandated references (Home Depot on UPS, Zoro on FedEx) filled automatically

One screen for every order

Orders land in Rilk the moment they are placed, with the shipping step on the order. Ship one order in a few clicks, or bulk-ship up to 500 orders in one batch. Each label prints to your label printer, the tracking number goes back to the marketplace, and the cost lands on the order.

What's included

Several UPS and FedEx accounts per company, each rate labelled by account
Third-party billing to a retailer's UPS or FedEx account, set per marketplace
Live rates from your own UPS, FedEx, USPS and DHL Express accounts
Automatic pick of the cheapest rate that arrives on time
Amazon Buy Shipping, with an "every Amazon order" setting
Walmart Buy Shipping next to your own rates, with fallback to your carriers
FedEx account registration inside Rilk, and FedEx One Rate
Bulk shipping up to 500 orders per batch
Tracking pushed back to the marketplace automatically
Label reference fields you set per marketplace
Label cost written to the order and its profit
USPS address validation, automatic on eBay and local-store orders by default
Reprint and void

Sources

Every statement about another company's product or price on this page comes from its own public pages, checked as of October 2026. Products change; if something here is out of date, tell us at support@rilk.ai and we will fix it.

Frequently asked questions

What shipping software supports multiple FedEx or UPS accounts?

Rilk. Connect as many UPS and FedEx accounts as you have. Every rate shows which account it comes from, so you compare your old account, a promo account and your negotiated rates on the same order and buy from the cheapest.

Can I ship a retailer's orders on the retailer's UPS or FedEx account?

Yes. Enter the retailer's account number once, per marketplace; you do not need its login. Rilk bills that retailer's orders to its account as third party, and it uses whichever of your own accounts you chose to make the label.

Can I use my own negotiated carrier rates?

Yes. Connect your own UPS, FedEx, USPS and DHL Express accounts and you see your own rates, with nothing added by Rilk. Amazon and Walmart Buy Shipping rates show next to them on those orders.

How does Rilk find the cheapest shipping label?

It waits for every connected carrier to answer, then picks the cheapest rate that still arrives on time. On a tie it takes the faster one. If nothing arrives on time, it tells you instead of buying a late label.

Can Rilk make every Amazon order ship with Buy Shipping?

Yes. Turn on "Buy Shipping only" and Rilk ships every Amazon order on Amazon Buy Shipping. The automatic pick, bulk shipping and the rate screen offer no other label for those orders.

Does Rilk support Walmart Buy Shipping?

Yes. Walmart's rates show next to your own carrier rates on Walmart orders, and you buy whichever is cheapest. The label, tracking and ship confirmation all go through Walmart's API without leaving Rilk.

Can I set what goes in the label reference fields for each retailer?

Yes. Per marketplace, you choose what fills each reference field: the channel PO, the order number, SKUs, quantity and SKU, your own SKU, notes and more. A default covers every other channel. Rilk fits it into each carrier's limits: 2 lines of 35 characters on UPS, 3 lines of 40 on FedEx.

Is there a per-label fee?

No. You pay the carrier or the marketplace for postage and nothing to Rilk per label. Labels are included within your plan's monthly order allowance; on the free plan that is 500 orders a month.

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