To choose the right 3PL partner, write down your order profile, then make every finalist prove four things before you sign: their technology and reporting in a live demo, SLAs in writing backed by a real peak plan, an all-in price built on your own order data, and an onboarding plan with a named owner for each step. When you score them, weight reliability above price.
A fulfillment partner that misses ship times or picks the wrong item costs more than its quote. You pay the difference in reships, refunds, "where's my order?" tickets and customers who don't come back.
These steps work whether you're hiring your first 3PL or replacing one that keeps losing inventory. They're the same checks we expect brands to run on KSP's 3PL fulfillment services. If you're still deciding whether to outsource at all, start with our comparison of in-house fulfillment vs a 3PL.
Before you compare providers, write down what success looks like for your business. Send the same list to every 3PL on your shortlist so their answers line up.
Without this list, you'll end up comparing 3PLs on pick fee alone, and that's where the expensive mistakes happen.
A 3PL can look great on a sales call and still run your inventory on spreadsheets. Ask every finalist to show you their systems on screen before you talk price.
Confirm the 3PL runs a warehouse management system (WMS). Some still work from Excel or software built in the '80s and '90s, which slows the floor down, invites manual errors and keeps you from seeing inventory and orders in real time. Ask about the transportation management system (TMS) too. It applies your customers' shipping rules and rate-shops each package across carriers when it's ready to go.
Then have them demonstrate the connections you'll depend on: Shopify and your other storefronts, Amazon, your ERP, and EDI if you sell to retailers. At a minimum, you need:
Ask for a live demo of the client portal. Watch how you'd check stock on a SKU, find a stuck order and see an exception, then ask what alerts you'll get and how an issue gets escalated. Ask for a real monthly client report with the client's name removed, and ask how much of it you can customize. You'll run your fulfillment off this data every week, so judge it on the reports they actually send clients.
What to ask:
KSP runs on Logiwa WMS with a 24/7 client portal, an open API, 100+ integrations and SPS Commerce EDI for retail orders. See the Shopify, Amazon and ERP integrations we connect.
A 3PL that fits at 200 orders a month can fail at 2,000 or 20,000. Ask for the numbers in writing and for examples from peaks they've already run.
For each one, ask how they track it, how you'll see it, and what happens when they miss it. "We're usually pretty fast" without a number is a red flag.
Ask for specific examples of how they handled volume spikes for brands like yours, plus the contingency plan and staffing plan they used. Then ask:
Your 3PL is the last touchpoint before the product reaches your customer. Ask them to walk you through their process, staffing model and automation, and ask to see:
KSP picks with 60 Locus robots and adds robots in blocks of 25 for peak. Every touch is barcode-scanned against a 99.999% order accuracy standard, and orders in by 2 PM CST ship the same day.
Ask to meet the account manager who would run your business. Find out how many other accounts they manage, how fast they respond and how an issue gets escalated. Some 3PLs limit clients to ticket queues or bots, which is slow when you need an answer on replenishment, a shipping exception or a carrier problem that afternoon.
Pay attention to the sales process too. If it takes three follow-ups to get a straight answer before you sign, it won't get faster once you're a client.
Talk to current clients, ideally brands with a similar order profile that went through a peak with this 3PL. Ask how onboarding went, how well the 3PL communicated, how they managed inventory accuracy and how quickly the program stabilized. Then ask about a time the 3PL was under pressure (a shipping delay, an inventory discrepancy, a broken integration) and what they did about it. Before you sign, ask how lost or damaged inventory is handled and what 3PL warehouse insurance covers.
Visit if you can. A walk through the floor shows you how the team works and how organized the operation is. If you can't travel, ask for a virtual tour or photos. A good 3PL will say yes.
KSP's account managers work on site, 30 feet from the pack line. When a premium linen brand moved to KSP from a 3PL that took weeks to fix receiving errors, issue resolution dropped to about 10 minutes. Ask for a tour of our Brooklyn Park warehouse when you request a quote.
The most common mistake is choosing the lowest pick fee without pricing the whole program. Many 3PLs keep a few line items low and recover the margin in storage, special projects and accessorial charges that only show up once your program is live.
Send every finalist the same data: SKU dimensions and weights, orders per month by channel, items per order, peak months and returns volume. Ask each one to price a typical month and a peak month from that data. Then lay the quotes side by side using each provider's own rate definitions, so a "per order" fee from one 3PL is compared with the same work from the other.
If a quote leads with a low per-pallet storage rate, ask what else gets billed per pallet: receiving, appointment fees, long-term storage and minimums. Then ask the questions that show what the invoice will look like:
A low outbound fee says little about efficiency. Sometimes the margin has moved into storage or accessorials. Sometimes it reflects low wages, and a 3PL paying below its local labor market struggles to keep experienced people, which shows up in your accuracy and ship times. The problem shows up at peak. If the rates were never built to cover peak labor, that 3PL won't authorize overtime, temps or extra equipment when your volume doubles, and your orders wait.
Ask whether the 3PL rate-shops each package and whether it passes along the carrier discounts it negotiates on the combined volume of all its clients. Get its policy on surcharges in writing. On the contract, read the term, the exit terms and notice period, who owns your data, and what remedy applies when an SLA is missed.
KSP rate-shops every package across USPS, FedEx, UPS, DHL and regional carriers at discounted rates, and ships to 220+ countries.
Slow returns tie up sellable inventory and drag out refunds. Look for:
What to ask:
Location sets your transit times and shipping cost. Weigh four things: how close the warehouse is to your own team, how far it sits from your manufacturer or port, where your customers are concentrated, and whether you need more than one distribution center. Most brands need one or two. Every added warehouse splits your inventory and adds receiving, transfers and counts to manage, so ask each 3PL to map its network against your customer data before you add one.
KSP ships from one central warehouse: ground delivery anywhere in the contiguous US in 1–3 days, and nationwide 2-day delivery through overnight service, without splitting your inventory.
Ask what onboarding looks like week by week and who owns each piece: the integration, SKU and kit mapping, inbound inventory, test orders and go-live. A plan with no named owner for the integration and mapping is a red flag.
Your integrations and the number of channels you run set the timeline. Unless you need a custom technology integration, be wary of a 3PL quoting several months to a year to onboard. A timeline that long usually means their platform is behind, and you pay for the delay.
KSP has integrated a new customer one day and shipped their orders the next. When a brand needs to leave its current 3PL fast, we can switch them in 3 days or less, depending on their integrations and how long the inventory takes to transfer.
Use this as your internal scorecard for every finalist.
☐ Proven pick accuracy process
☐ Clear receiving SOP and timeframe
☐ Peak season plan and staffing strategy
☐ Standard packaging and fragile-item SOPs
☐ Kitting and bundling capability (if needed)
☐ Shopify integration and tracking sync
☐ Client portal, shown in a live demo
☐ Real-time inventory visibility
☐ Reporting exports and custom reports
☐ Warehouse locations match where your customers are
☐ Carrier options fit your package profile
☐ Clear policy on rate shopping and surcharges
☐ Fast returns processing and restock logic
☐ Photo inspection or damage documentation
☐ Exchange workflows if your CX requires them
☐ You've met the account manager and know the escalation path
☐ Reference calls with clients like you
☐ Week-by-week onboarding plan with named owners
☐ Transparent pricing sheet with definitions
☐ Contract terms you can live with
☐ Account support expectations defined in writing
Score each finalist across these buckets:
If a 3PL wins on price but loses on reliability, you'll usually pay the difference, and more, in refunds, reships, lost customers and support load.
KSP is a veteran-owned 3PL founded in 2012, and we've shipped 32.1 million orders. Here's how we answer the checks above:
What should I prioritize first when choosing a 3PL: cost or delivery speed?
Prioritize reliability first: pick accuracy and SLAs the 3PL hits every week. Then work on cost. A cheaper 3PL that misses ship times or picks the wrong items costs more overall, because you pay for reships, refunds, support tickets and customers who don't reorder.
How many warehouse locations do I need?
Most brands need one or two fulfillment centers. Add a location only when your customer map and delivery promise call for it, because every extra warehouse splits inventory and adds receiving and transfer work. KSP ships from one central US warehouse, with ground delivery anywhere in the contiguous US in 1–3 days.
What's the biggest hidden cost with a 3PL?
Storage, receiving and extra operational fees: labels, inserts, returns handling, special projects and accessorial charges. A low pick fee often sits next to high storage or receiving rates. Ask every finalist to price a full typical month from your own order data, then compare the totals.
How long does 3PL onboarding take?
Onboarding should take days to a few weeks unless you need a custom technology integration. Your integrations and where your inventory sits today set the timeline. KSP can switch a brand from another 3PL in 3 days or less when needed, and has shipped a new customer's orders the day after integrating.
How do I choose a fulfillment provider with good reporting?
Ask for a live client portal demo and a real monthly client report. Check that you can see inventory and order status in real time, get alerts on exceptions, export your data and build reports around the metrics you track. Treat a provider that can only describe its reporting as a red flag.
Should my 3PL handle returns?
Yes, if they process returns quickly, document item condition and show you every return in their system. Slow returns processing ties up sellable inventory and drags out refunds. Ask for their average time from return arrival to restock, and whether they track return reason codes.
What if I sell on Shopify and Amazon?
Choose a 3PL that runs both channels from one inventory pool, with accurate sync and clean exception handling for partials, cancellations and split shipments. If Amazon is a key channel, ask specifically how they handle FBM requirements and whether they prep FBA shipments in the same building.