I just reviewed something that many overlook when talking about the maximum supply of Bitcoin. Most say "21 million BTC and that's it," but the reality is much more complex than that.

You see, the 21 million limit is fixed, that's clear. What varies is how much of that Bitcoin is actually available on the market. According to current data, we have about 20 million BTC already mined, but here’s the interesting part: a significant portion of those coins has been lost forever or is dormant in wallets abandoned by their owners years ago.

Think of it this way. In 2012, when Bitcoin was still very young, about 10.5 million BTC had been mined. Most circulated freely because people were still figuring out what to do with them. Then came 2016, and the landscape changed. Over 800,000 BTC were already out of circulation, mainly due to forgotten keys or discarded hard drives. By 2024, that number grew to 2.3 million coins that simply disappeared from active circulation.

What’s fascinating is that this creates a structural deflationary effect. As the issuance of new BTC follows the halving protocol and approaches zero, lost and dormant coins continue to accumulate. This means that the effective circulating supply could reach a maximum at some point and then start to decrease, even though technically there are always 21 million BTC existing on the network.

Looking ahead, the numbers suggest something important: by 2030 or 2040, the gap between the total supply and the actually usable supply could be huge. If the current pattern continues, we might end up with only 7 to 8 million BTC effectively available for transactions by the year 2100.

This completely changes how we think about Bitcoin scarcity. It’s not just that it’s limited to 21 million; in practice, the amount that actually functions as money could be significantly lower. That’s the real deflationary angle that few are analyzing in depth.