# How do you build a subscription box on Shopify where customers pick the items? > Source: https://zubs.app/features/build-a-box > Title: Build-a-Box Subscriptions on Shopify — Zubs > Published: 2026-10-02 > Updated: 2026-10-07 > Language: en ## Short answer With Zubs, customers subscribe to one box product and choose what goes inside it: on the product page before checkout, and in the customer portal for every order after that. You decide how many items a box holds or what it must be worth, which products are on the menu and when. ## How does build-a-box work? A [build-a-box subscription](https://zubs.app/glossary/build-a-box) runs on one Shopify product that stands for the box itself, not for anything in it. Customers subscribe to the box, and the items they pick are added to each upcoming order. You decide what a box means: a set number of items, such as 5 in a small box and 10 in a large one, or a minimum value it has to reach before it ships. The menu comes from Shopify collections you already manage, so curating it needs no new tool. A common setup gives the first box away at checkout and uses a [Sequential Flow](https://zubs.app/features/sequential-flows) to set the regular price from the next order. Signing up then costs nothing, and the first real box is the first charge. ## How do customers pick their first box? On the box's product page, before checkout. Customers browse your collections in one grid, add items with plus and minus buttons and see how many they have left or how close they are to the minimum. They also see when their first box arrives. Then they check out through Shopify's own checkout, and their picks land on the first order. You style the picker in the theme editor to match your store. Product cards can carry short labels, such as a diet tag or the number of servings, so customers can choose quickly from a long menu. ## Can the menu change every week? Yes. You schedule a collection for the weeks it should appear, and its products show up only for boxes billing in that time. A weekly menu becomes a set of collections, each planned for its week, while staples without a schedule stay on the menu all the time. You can preview what each week's menu will look like before it goes live. A changing menu also keeps the box from turning into routine. When there is something new to pick, subscribers look forward to the next box instead of asking whether they still need it. ## What if a customer doesn't pick? Busy customers forget, so Zubs has a safety net. It can fill empty slots from the same menu before billing, using only products still in stock, and the customer can still swap them until your cutoff. A box that stays empty can be skipped instead of charged, so nobody pays for nothing. ## How does it fit with the rest of Zubs? After the first box, customers fill every upcoming one in the [customer portal](https://zubs.app/features/customer-portal), and can plan several boxes ahead. Each [subscription plan](https://zubs.app/features/subscription-plans) can bring its own menu and rules, which helps when one store runs two different boxes. Changes lock a set number of days before billing, so your kitchen or warehouse works from a final list. If boxes are collected rather than shipped, [pickup locations](https://zubs.app/features/subscription-pickup-locations) work with the same setup. Set it up in the help center: [build-a-box subscriptions](https://help.zubs.app/docs/subscription-management/build-a-box/). ## Who is it for? Merchants whose customers want a say in what arrives: meal kits, snack and beauty boxes, farm boxes and curated product boxes. It suits weekly programs with a changing menu as well as monthly boxes with a fixed number of picks. ## Bottom line Build-a-box in Zubs covers the whole loop: customers pick their first box on the product page, change every box after that in the portal, and choose from a menu that follows your calendar. You run it with Shopify products and collections, without custom code. ## Frequently asked questions ### Can customers change their box after checkout? Yes. In the customer portal they change any upcoming box until your cutoff before billing. ### Can I offer a small and a large box? Yes. Each box size can include its own number of items or have its own minimum value. ### What if a customer never picks anything? Zubs can fill the empty slots for them before billing, and a box that stays empty can be skipped instead of charged. ### Can products be on the menu only in certain weeks? Yes. You schedule collections for the weeks they should appear, and staples stay on the menu all the time. ### Do I need custom code? No. You build the box from Shopify products and collections and add the picker in the theme editor. ## Related - [Industry: running a meal kit subscription](https://zubs.app/solutions/meal-kit-subscriptions) - [Customer story: noms+ adds customer portal add-ons](https://zubs.app/customers/nomsplus) - [Feature: the customer portal where customers change each box](https://zubs.app/features/customer-portal) - [Feature: subscription plans, prepaid, anchors and cutoffs](https://zubs.app/features/subscription-plans) - [Calculator: what each box earns you](https://zubs.app/tools/subscription-box-profit-calculator) - [Help center: set up build-a-box subscriptions](https://help.zubs.app/docs/subscription-management/build-a-box/)