600k orders in a single week for Kinderpostzegels with Shopify Plus

When the Dutch charity Kinderpostzegels wanted to digitize their organization, they needed a dependable tech partner to handle their yearly traffic peak. Every autumn, as school children go from door to door to sell limited edition stamps and collect donations, their site processes close to 600.000 orders in a single week - with a little help from Shopify and Code.





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Processing 3.5 million euros in a day

The yearly Kinderpostzegelactie is a well-known phenomenon in the Netherlands. It was set up a century ago when the Dutch government issued so-called ‘children’s stamps’ that cost a little extra, so that the profits could be used to help disadvantaged children. Every year, at the beginning of the new school year, school children all over the country go door to door to collect orders for the newly issued stamps, which are then delivered by mail.

In recent years this process has increasingly gone digital. The 2023 edition saw 35% of the orders coming in on paper forms and 65% via the Kinderpostzegels online store. In the charity’s easy-to-use webshop, people can place their orders while standing at their front door: by scanning their seller’s unique QR code. 


As you can imagine, this leads to a huge surge in traffic. Eva de Koning, Senior Project Manager at Kinderpostzegels, has witnessed it a few times now: “On the first day of the event, the moment primary schools are out, our traffic shoots into overdrive. Typically we receive half of the event’s proceeds on the first day, around 3.5 million via the store and c. 1.3 million EUR via paper forms.”

Does your store regularly crash when a sales peak hits? It might have to do with your platform: at Code we hear this complaint a lot from brands using Magento or Shopware.



From paper to digital

To enable the shift to digital, for the past couple of years Kinderpostzegels has worked hard to streamline and automate the process. In 2022 they asked us to upgrade their existing Shopify webshop to Shopify Plus, and rebuild it in such a way that people just need a few clicks to place their order or make a donation. 

This also meant reducing the number of products. Eva explains: “We’ve been seeing a big shift from physical products to donations, from 11% donations three years ago to 40% in 2023. Hence, we now offer three donation products alongside the tangible products.”

Other features Code added are the personalized QR codes every stamp seller now receives, so their sales can be tracked and top sellers can be rewarded for their efforts; and the donation checkbox in the checkout, which enables customers to round off the total amount due and donate the surplus. 

In addition, Kinderpostzegels asked Code to build a few custom integrations: one to forward orders to their fulfilment partner, and another one to import the data from the digitized paper forms into Shopify - so as to create a ‘single source of truth’. Eva: “Every year around 120.000 children participate, using both their personal QR code and a set of paper order forms. The filled-out forms are collected by their teachers and sent to us. To process them we need to put those orders in our Shopify database, together with the digital orders.” From there, customers receive payment requests, orders are fulfilled, and accounts can be accessed by the customer care department.

How to manage a high-volume sales peak: A day in the control room

Typically, the first day of a new action is a big event for the people at Kinderpostzegels, and they prepare accordingly. The people coordinating it gather together in a control room that is set up for the occasion, Customer Care is at full strength, and technical specialists are on stand-by to ensure a smooth run. Sofie Vriends, President at Kinderpostzegels, describes the atmosphere as “very impressive. There’s a big dashboard in the room that shows which children are selling where and how much, in real time, and you can feel the adrenaline.” 

In 2022, when Code’s new Shopify store was first put to the test, Coder Dominick was present to help with any technical hiccups and ensure the new set-up worked as it should. As it turned out, the only weak link was the external Payment Service Provider Kinderpostzegels used. Jeroen, Kinderpostzegels’ Project Manager at Code, recalls: “Because the store suddenly processed thousands of payments, the PSP put a security lock on it. Dominick was able to switch it to Shopify Payments and get it running again, but the site couldn’t process any payments for 1.5 hours.” Luckily, the children going door-to-door during that time could fall back on the paper forms, but it showed in that year’s stats: only 35% of sales were made digitally, and 65% through paper forms.

In 2023, Kinderpostzegels immediately switched to Shopify Payments after a hiccup, which led to a promising 60-40 division between paper and digital. In the same year we also collaborated with Kinderpostzegels to replace their legacy ERP system with a more flexible tech stack, which was a huge operation that had to be finished in time before the 2023 Kinderpostzegelactie. Eva: “It went very well! The spiking traffic was no problem; Shopify just quietly scaled along in the background without us having to manage anything.”

KZP behind the scenes
KZP sales

Working with Code

Eva is very pleased with Shopify Plus and Code. “They say what they do and they do what they say: I've yet to see them overlook or forget something. Our Project Manager Jeroen is very structured and accurate. In general, I find Coders approachable and attentive: the first question is always ‘How was your weekend?’ before we move on to business. And their team is stable over time, which isn’t always the case with agencies. Because of that they know your situation and what works for you.” 

In 2024, Code and Kinderpostzegels will continue to improve the store - we’ll keep you posted!

Having problems when traffic spikes? Shopify and Code can help you with that!