Know when switching is the right call
Switching apparel 3PLs makes sense when the problems are structural rather than occasional. One bad week during peak is not a reason to move. A pattern is.
- Wrong sizes or colorways keep shipping, and the fix offered is always more training rather than scan verification.
- Returns sit for a week or more before they are processed, so sizes show as out of stock while units sit in a cage.
- Drops and launches routinely miss the ship dates you promised customers.
- Retail partners are issuing chargebacks for labels, ASNs or carton contents.
- You cannot see inventory by size and color without asking someone to pull a report.
If two or more of these describe your current provider, the cost of staying usually exceeds the cost of a well-planned move. Write the problems down. They become the requirements you test every candidate against.
Pick the window before you pick the provider
The best time to switch apparel 3PLs is during your slowest selling period, with enough runway to finish before the next launch or peak. For most clothing brands that means avoiding October through December, the weeks around major drops, and back-to-school if you sell kids or uniforms.
Work backward from the date you need to be stable. A typical migration needs time for contract and integration setup, a test period, the physical inventory move and a few weeks of settling in. Leave a buffer between go-live and your next big release so any receiving variances or mapping errors surface on normal days rather than launch day.
Also check your current contract. Notice periods, minimum terms and fees for removing inventory affect the timeline and the budget, and some agreements require written notice well ahead of termination.
Clean your product data first
Clean product data is the single biggest factor in a smooth apparel migration. Every style, size and color must exist as its own SKU with a unique barcode before a single carton moves.
- Export the full variant list from your storefront, ERP or PIM, including discontinued styles that still have stock.
- Confirm every variant has a UPC or internal barcode that matches what is physically on the hangtag or polybag.
- Standardize size naming. If one style uses "XL" and another uses "X-Large", decide which wins.
- Add weights and dimensions per variant, folded and packed, because shipping rates and carton selection depend on them.
- Flag styles that need special handling: hanging storage, tissue, inserts, kits or bundles.
The new warehouse can only be as accurate as the item master it receives. Fixing data now is far cheaper than fixing mis-shipped orders later.
Map integrations and channels
Integration mapping means every place an order can come from, and every place inventory must be reported, is connected and tested before go-live. For apparel brands that list is often longer than expected.
List each storefront, marketplace, wholesale platform, subscription app, returns portal and EDI trading partner. For each one, confirm how orders flow in, how tracking flows back, and how inventory levels sync. Pay particular attention to bundles and kits, since a storefront bundle SKU has to break down into the correct component sizes on the warehouse side.
If you ship to retailers on EDI, plan to re-certify with each trading partner. Many retailers require test transactions for purchase orders, advance ship notices and carton labels whenever the shipping location or provider changes. Start that early, because retailer testing calendars rarely match yours.
Plan the physical inventory move
The physical move works best when inventory is split into waves rather than shipped all at once. Send your fastest-moving sizes and core colorways first so the new location can start fulfilling the bulk of orders while slower stock follows.
- Ask the outgoing warehouse for a carton-level packing list by style, size and color.
- Send an advance ship notice to the new warehouse for every truckload.
- Expect a full count at receiving, with variances reported by variant before stock goes live.
- Keep hanging garments on hangers if they will be stored that way, to avoid steaming everything on arrival.
During the overlap, both locations may be shipping. Decide in advance which orders route where, and set storefront inventory so you never sell units that are in transit on a truck.
Cut over returns cleanly
Returns are the most commonly forgotten part of an apparel migration. Customers who bought before the switch will keep sending items back to the old address for weeks.
Update the return address in your returns portal, packing slip templates and help center on the day the new location starts shipping. Arrange for the outgoing warehouse to keep processing or forwarding returns for a defined period, and agree on how those units get transferred. Make sure your grading standards, refurbishment steps and restock rules are documented and handed to the new provider, so a Grade B garment is treated the same way it was before.
Exchanges deserve extra attention. If exchanges ship on return scan, the trigger has to fire from whichever building receives the return.
Go live, then watch the first 30 days
Going live is the start of the migration, not the end. The first month is when small mapping issues show up as real customer orders.
Track a short list of signals daily: orders shipped versus received, wrong-item complaints, inventory variances by variant, return processing time and any retailer compliance notices. Review them with the new provider every week. A good apparel partner will raise problems before you find them.
Keep the old account open with a small amount of stock or a forwarding arrangement until the numbers settle. Close it only when inventory has been fully reconciled and the last stray returns have been accounted for.
Frequently asked questions
How long does it take to switch apparel 3PLs?
Switching apparel 3PLs typically takes several weeks to a few months, depending on catalog size, number of channels, retail EDI re-certification and how clean your product data is. Planning around your slow season gives the most room.
Will I have stockouts when I move inventory?
You can avoid most stockouts by moving inventory in waves, fastest sizes first, and by holding storefront availability for units in transit. A short overlap where both locations ship keeps orders flowing.
Do I need to redo retail EDI testing when I switch warehouses?
Usually, yes. Many retailers require new test transactions for purchase orders, advance ship notices and carton labels when your ship-from location or provider changes, so start that process early.