An inventory management system tracks stock, purchase orders and product costs across every place you sell. A single-channel Shopify store can now run on Shopify’s native tools. Add a dedicated system when a second channel, location or assembled product arrives, and save ERP for wholesale-heavy operations.
Shopify did not stop managing your inventory on August 31, 2026. It stopped letting one free app pretend to cover your second channel, your landed costs and your reorder math at the same time.
When I ran app audits for merchants during my years at Shopify, I kept finding duct tape: point solutions nobody could explain, stitched together by manual updates. Guests on the podcast describe the same thing underneath, a spreadsheet that one person maintains and everyone else quietly trusts. That setup works right up until the brand adds a wholesale account, a pop up, or an Amazon listing, and then the spreadsheet becomes the reason orders oversell and cash sits in the wrong products.
That pattern has become more urgent. Shopify retired Stocky, its free purchasing and forecasting app, on August 31, 2026, and a large group of merchants who never chose an inventory system suddenly had to. At the same time, inventory data now feeds the product listings that Google and AI shopping assistants decide whether to show.
This guide is for the merchant in the middle: past the first $250K, not yet running a $50M operation, and trying to work out whether the next step is a better spreadsheet, Shopify’s own tools, a dedicated inventory platform, or an ERP. If you are just starting, the first two sections are the ones to read closely. If you are scaling across channels, the tier table and the worked example are where I want you.
An inventory management system is the software that keeps one trusted record of what you own, where it sits, what it cost, and when to reorder it, then pushes that record to every channel you sell on. For a Shopify brand, that comes down to four jobs: accurate counts by location, purchasing from suppliers, true product cost, and syncing available stock to each storefront and marketplace so you do not sell what you do not have.
Shopify’s own enterprise team described the problem well in its guide to inventory management systems for Shopify Plus brands: high-growth merchants often manage stock through a mix of spreadsheets, several apps and one-off workarounds, and the mix breaks as they grow across the online-to-offline (O2O) divide. Dedicated software for managing inventory exists because those workarounds do not scale with the number of places a product can be sold.
The fourth job is the one most merchants underrate. Riikka Söderlund, COO of Katana, made the point on episode 455 of the eCommerce Fastlane podcast that Google’s Shopping Graph uses inventory as one of the data points that decide which products get shown. A store whose stock levels are wrong or stale is not just risking an oversell. It is sending bad signals to the surfaces that now drive discovery, including the AI shopping assistants that pull from the same product data.
The second underrated job is cost. Revenue reports tell you what sold. They do not tell you whether each order made money once freight, packaging and duties are counted. Söderlund described brands that only came to Katana after realising they had been selling at a loss without knowing it. A real inventory management system earns its keep as much on that margin visibility as on counting units.
Whether you are doing $10K months or $1M months, those four jobs are the same. What changes with scale is how many channels, locations and product types each job has to cover, and that is what decides which tier of tool you need.
Shopify retired Stocky on August 31, 2026, after delisting it from the App Store on February 2, 2026, and moved most of its everyday functions into the Shopify admin. According to Shopify’s Stocky transition guide in the Help Center, merchants keep read-only access to export Stocky data for at least 90 days after retirement, and Stocky’s APIs stopped working on the retirement date.
Here is what the admin now covers natively. Purchase orders support supplier assignment, CSV line item import, payment terms and receiving through a linked transfer, though you cannot email a purchase order from Shopify, so you download a PDF and send it yourself. Transfers move stock between locations in the admin and in POS, including partial shipments. Each variant can have one bin location per site, but moving stock between bins needs a third-party app. Inventory stock counts let you plan a count, have staff count in parallel and have a manager approve the result before levels change. Sidekick, Shopify’s AI assistant, can help forecast demand and draft purchase orders or transfers.
Here is what it does not cover, according to that same page. Weighted average costing and landed costs point you to a third-party app. There is no native report for total spend by supplier. Historical Stocky purchase orders, stocktakes and cost data do not migrate, which is why the export matters more than any feature comparison.
On the podcast, I put the size of the Stocky user base at roughly 120,000 merchants, and Söderlund described Stocky’s retirement as “a symptom of the shift that is happening in market and inventory management becoming more and more and more complex.” I think that framing is right. For a one-location store, the native tools are a genuine upgrade over what Stocky offered. For a brand that bundles products, sells wholesale, or needs landed cost on every unit, the retirement removed the free middle layer and forced a decision that was probably overdue.
If you used Stocky, do two things this week whatever else you decide: export everything while the read-only window is open, and write down which Stocky reports you actually opened in the last six months. That list, not the vendor feature grid, is your requirements document.
You need a dedicated inventory system when your operation adds a second sales channel, a second stocking location, assembled or bundled products, or occasional wholesale orders, regardless of revenue. Revenue is a weak proxy. A $4M brand selling one product range on one storefront from one 3PL can run happily on native tools, while a $700K brand selling on Shopify, Amazon and at markets, with gift sets assembled in house, cannot.
Two guests on the podcast, building very different products, landed on the same answer. Söderlund described the moment a merchant adds TikTok Shop, Amazon or a brick and mortar presence, and said “the amount of complexity that that one additional location and sales channel actually adds to your inventory operation. It often comes as a surprise to the merchant.” The questions that were easy on one channel (what do I have, where is it, when do I reorder) get harder with every channel you add.
Kyle Hency, co-founder and CEO of GoodDay and co-founder of Chubbies, told me on episode 399 of the eCommerce Fastlane podcast that of the 20 or so customers GoodDay had at the time, “19 of 20 manage their business on Excel spreadsheets, a handful of operating point solutions in QuickBooks.” He was blunt that the right fit depends on the operation, not the size: one sales channel and one SKU was not a fit for his product, and adding sales channels alone adds a lot of complexity.
Söderlund put the spreadsheet problem more vividly: “You wouldn’t believe how big of a company will run their inventory on a spreadsheet that doesn’t update, that doesn’t link to anything that is not connected, it’s not online. It sits on a desktop somewhere underneath the CEO’s table.”
It is easy to misread this in both directions. A brand can buy an ERP at $1M because a peer did, then spend a year feeding a system its team cannot maintain. Another can stay on spreadsheets at $8M because nothing has broken yet, while stockouts and dead stock quietly cost it money. Katana’s survey of 375 product brands, which we broke down in what Katana’s 375-brand stockout study actually measured, put the median annual stockout loss at roughly $21,000 among brands that already ran inventory software. Treat that as a floor for brands with tools, not a forecast for yours.
Inventory tools fall into four tiers today: Shopify’s native tools, dedicated inventory platforms, warehouse or 3PL led systems, and ERP. Each tier solves a specific kind of complexity, and the mistake is not picking the wrong vendor inside a tier so much as picking a tier above where your operation actually sits.
Native tools are the right answer for more stores than vendors will tell you. If you resell finished goods from one location and your counts are accurate, the admin’s purchase orders, transfers and stock counts cover the core jobs. Add barcode discipline first; our guide to barcode inventory management for Shopify stores covers unique barcodes per variant and the scanning habits that keep counts honest.
A dedicated inventory platform earns its cost when you add the second channel or start assembling what you sell. That is where multichannel stock sync, bills of materials and landed cost start to matter. Warehouse led systems make sense when picking, packing and shipping are the constraint, and often come bundled with a third-party logistics (3PL) relationship.
An ERP system belongs to the brand that runs wholesale prebooks, multiple legal entities or a finance team that needs inventory, purchasing and accounting in one ledger. If you are not there, the cost is not just the licence. It is the months of process change your team absorbs instead of selling. And if routing orders across stores and warehouses is your real problem, that is an order management question; see where Shopify’s native order routing runs out.
The shortlist for most growing Shopify brands today is Katana for makers, Cin7 for multichannel resellers, Shopventory for retail-heavy stores, ShipBob or ShipHero when fulfillment drives the decision, GoodDay for ERP lite with wholesale, and NetSuite for enterprise ERP. Two names that still turn up on older shortlists have changed enough that following them would now mislead you.
Katana is built for brands that make or assemble what they sell, connecting raw materials, production and finished goods to Shopify and accounting tools like QuickBooks. Söderlund described it on the podcast as connecting to a brand’s existing stack rather than replacing it. Our full Katana review for Shopify brands that manufacture covers plan costs and onboarding time; skip it if you are a pure reseller.
Cin7 suits resellers juggling Shopify, marketplaces, wholesale and retail from shared stock. It is also where Orderhive, which still appears on older shortlists, ended up: Cin7 acquired it, and it no longer takes new signups as a standalone product, so I would not start there today. Shopventory remains a fit for stores where physical retail and POS drive most of the volume.
ShipBob and ShipHero approach inventory from the warehouse out. If you already use, or plan to use, their fulfillment network or warehouse software, their inventory views may be enough, and you avoid running two sources of truth. The trade off is that your inventory record lives with your fulfillment provider.
GoodDay, which Hency walked through on episode 399, is an ERP lite system built inside the Shopify admin for brands with wholesale and more complex operating flows. NetSuite Inventory Management sits at the enterprise end, for brands that need full ERP and can resource the implementation. Finally, Stocky was Shopify’s free purchasing app for years. It is retired, and the replacement for most of what it did is now inside your Shopify admin.
Applied to one store, the tiers point a $1.5M brand selling on Shopify and Amazon with in-house gift sets to a dedicated inventory platform, not an ERP. What follows is a labelled composite, built from patterns guests have described on the podcast and from the brands I worked with at Shopify, not a real company, and none of its numbers are observed results.
Picture a skincare brand doing around $1.5M a year. It sells on its Shopify store and on Amazon, ships Shopify orders from its own small warehouse, and sends a portion of stock to Amazon’s fulfillment network. A third of its revenue comes from gift sets the team assembles in house before holiday. It used Stocky for purchase orders and keeps cost of goods in a spreadsheet the founder updates when a supplier invoice arrives.
Here is what I would look at, in order. First, the gift sets: they mean the brand needs to track components and finished bundles separately, which Shopify’s native tools do not do. Second, the second channel: Amazon stock and Shopify stock draw from the same purchasing budget, so reorder timing has to see both. Third, cost: with landed cost living in a spreadsheet, the founder cannot see which gift set loses money after packaging and freight.
My call is a dedicated inventory platform with bundle support and multichannel sync, moved in before the next holiday build, not an ERP. There is no wholesale, one legal entity, and no finance team that needs a unified ledger, so an ERP would be paying for complexity the brand does not have. What I would remove is the spreadsheet as a source of truth on the day the new system goes live, because running both is how counts drift apart.
Change one fact and the call changes. If the same brand signed three retail wholesale accounts with seasonal prebooks, I would move the ERP lite conversation forward a year. If it dropped Amazon and stopped assembling gift sets, I would tell it to stay on Shopify’s native tools and spend the money elsewhere.
Before you talk to any inventory vendor, audit your current apps, clean your product data, and write down the three decisions your inventory record has to support. That hour of work cuts most of the cost and risk out of the switch, and it sometimes shows you do not need to buy anything yet.
Start with the app stack. When I ran app audits for merchants at Shopify, the first question was always why each app was there. As I said on episode 455, “Many times I’ve had $500 a month apps that no one’s even using anymore and the team members left.” Inventory tools are especially prone to this: a forecasting app here, a bundle app there, a spreadsheet that feeds both. List every tool that touches stock, what it does, who owns it and what it costs.
Then clean the data you would migrate. Every sellable variant needs a unique SKU and barcode, every location needs an accurate count, and every supplier needs current lead times. If your counts are off today, a new system will just make the wrong numbers move faster; our explainer on what causes inventory discrepancies and how to prevent them is the right place to start.
Finally, write down the decisions the system must support: when to reorder each product, what each product truly costs, and how much stock each channel can safely show. Hency’s point on episode 399 applies to whatever you choose: “If you work really hard to maintain the integrity of the data, you’ll get more and more power out of a system.” If none of those decisions is going wrong today, the honest answer may be to stay on native tools, fix your counts and revisit the question when you add the next channel.
An inventory management system in ecommerce is software that keeps one accurate record of your stock across every location and sales channel, then uses that record for purchasing, costing and stock sync. It tells you what you have, where it is, what it cost, and when to reorder. For Shopify merchants, the system either runs inside the Shopify admin (native purchase orders, transfers and stock counts) or connects to it as a dedicated app or ERP. The right setup depends on how many channels, locations and product types you manage, not just on revenue. A single-channel reseller can run on native tools, while a brand selling on several channels with bundled products usually needs a dedicated platform.
Shopify’s built-in inventory is enough for many single-channel stores after Stocky’s August 31, 2026 retirement, but not for brands that need landed costs, weighted average costing or bundle tracking. The admin now includes purchase orders with supplier assignment and CSV import, transfers between locations, and inventory stock counts with manager approval, and Sidekick can help forecast demand and draft purchase orders. Shopify’s own transition guide points merchants to third-party apps for weighted average and landed costs, and notes there is no native supplier spend report. If you sell on one channel from one location and resell finished goods, start with the native tools before paying for an app.
A Shopify store should move from spreadsheets to inventory software when it adds a second sales channel, a second stocking location, assembled or bundled products, or wholesale orders. Those are the points where a spreadsheet can no longer keep counts, reorder timing and costs in sync, and errors start showing up as oversells, stockouts or dead stock. Revenue alone is a poor trigger: a large single-channel reseller can run on native tools, while a smaller multichannel brand cannot. Before switching, clean your SKUs, barcodes and counts, because a new system will only be as accurate as the data you migrate into it.
An inventory management system focuses on stock: counts, purchasing, product costs and syncing availability across channels, while an ERP combines inventory with accounting, purchasing, wholesale, and often manufacturing and HR in one system of record. Dedicated inventory platforms such as Katana or Cin7 usually connect to accounting tools like QuickBooks rather than replacing them. ERPs such as NetSuite suit brands with wholesale prebooks, multiple legal entities or finance teams that need one ledger, and they carry longer implementations and higher costs. ERP lite tools such as GoodDay sit between the two for growing Shopify brands with more complex operating flows.
Choose inventory software for a Shopify brand with Amazon and wholesale by matching it to your hardest operating problem: multichannel stock sync, bundles or manufacturing, fulfillment, or wholesale order management. Start by listing your channels, locations and product types, and the decisions the system must support, such as reorder timing and true product cost. Shortlist tools built for that problem: Katana for makers, Cin7 for multichannel resellers, ShipBob or ShipHero when fulfillment drives the decision, and an ERP lite or ERP when wholesale prebooks and finance requirements dominate. Ask each vendor to demo your own messiest workflow, not their standard script, and check how they handle data migration.
