Building an assortment is always a balancing act.
Stock too many familiar products and your shop can start to feel predictable. Buy too much newness and you risk tying up budget in products your customers do not connect with. A useful way to think about that balance is the 70/20/10 rule.
It is not a fixed formula, and it will not suit every store in exactly the same way. But as a starting point, it can help you think more clearly about how much of your buying budget goes towards what already works, what keeps your assortment fresh and what you simply want to try.
70%: the products you know you can rely on
The biggest part of your assortment should usually come from products and brands that have already earned their place. These are the pieces customers come back for. The categories that consistently sell. The brands you know work well with your audience. For one retailer, that could be a core selection of candles, ceramics and textiles. For another, it might be jewellery, stationery or childrenswear.
This is the part of your assortment that gives you stability. It also does not mean buying the exact same products forever. You can refresh colours, shapes or collections while staying within categories and brands that have already proven themselves.
The point is that most of your budget should not be riding on a guess.
20%: the newness that keeps things interesting
The next 20% is where you create movement.
This can include seasonal products, new collections from brands you already stock or new brands that still feel like a natural fit for your store. This is often the part customers notice first.
It gives regular visitors something new to discover and gives you a reason to refresh displays, create new content and bring a different mood into the shop.
The key is to keep this part connected to your existing assortment. A new product should still make sense next to the rest of your store. Newness works best when it adds something rather than completely changing direction.
10%: the experiments
The final 10% is where you give yourself permission to try something less certain.
This part should feel a little less predictable. Not every experiment will work, and that is fine. The goal is not to be right every time. It is to learn what else your customers might respond to. Sometimes that 10% is also where your next bestseller comes from.
Why this works
The strength of the 70/20/10 approach is not really in the percentages. It is in the way it forces you to think about the role each product plays in your assortment.
Some products are there to sell consistently. Some are there to create freshness. Some are there because you want to test an idea. Without that distinction, it is easy to end up with too many products doing the same job.
You might realise that your shop is too dependent on safe choices. Or the opposite, that too much of your budget is going into products you have no sales history for. The framework simply gives you a way to check the balance.
Adjust it to your store
A gift shop with steady year round traffic might be comfortable with a larger core assortment. A concept store built around discovery might want more room for seasonal products and experiments. A retailer heading into Christmas might temporarily shift more budget towards seasonal stock.
That is why the percentages should be treated as a guide, not a rule. You could work with 80/15/5, 60/30/10 or something completely different. What matters is knowing how much of your assortment is dependable, how much is new and how much is genuinely experimental.
Test before you go deeper
The experimental part of your assortment does not need to involve a huge order.
Smaller first orders can help you see whether a new brand or product category deserves more space. If it performs well, you can reorder and gradually move it into the part of your assortment you rely on. If it does not, you have learned something without committing too much budget.
This is often a better way to discover what works than trying to predict everything before the season starts.
A simple check before your next buying session
The next time you review your assortment, look at what is already in your shop and ask yourself three questions.
- What do I know works?
- What feels new but still fits my customer?
- What am I genuinely testing?
If almost everything falls into one of those three groups, you probably have a healthy mix. A good assortment needs familiarity, but it also needs enough change to give customers a reason to look again. The goal is not to follow 70/20/10 perfectly - it is to make sure your buying decisions are balanced on purpose.
.svg){kind=small}
