62% of Spanish grocery volume is private label. And the market leader just lost its growth crown.
In the first 16 weeks of 2026, Lidl and Aldi grew share by 0.3% each. Mercadona grew by 0.2%. Mercadona still holds 37%, but Lidl hit 8.2% and Aldi 2.7% (Data by Algori).
Why the slowdown for Mercadona? I see two theories.
First, the ceiling effect. When you control 37% of the market, fast growth is mathematically hard. It is a logical slowdown.
Second, the recent viral videos showing empty fresh food shelves at Mercadona at the end of the day. A man walks in to buy vegetables, finds empty boxes, and goes straight to Consum next door.
We must separate assumptions from facts. Viral supply chain issues definitely hurt trust. But a few videos do not shift national market share alone.
This is a possible hard structural shift, not just a temporary stock issue. The German discounters opened over 90 physical stores last year. They are buying share aggressively.
I will trace the situation as new data comes in.
What is your opinion? Is Mercadona just hitting a natural ceiling, or are they actually losing their edge on the shop floor?