The current maximum is **2000**, for both Items and Pokemon storage.

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Originally, it was 1000. As others have also, I fully upgraded mine. I can also confirm that the price stayed the the same for every upgrade purchased to the maximum.

Here is a screenshot of my storage at 1000 each, and the message I got after trying to buy another upgrade once the cap was reached:

[![Your storage is fully upgraded][3]][3] 

Is it worth maxing Pokemon storage? It really does come down to this: for most people, this is NOT necessary. It simply fits the way I wanted to play Pokémon GO. I am not interested in having the highest CP Pokémon or battling Gyms for the time being. I simply enjoy playing "my way", I don't see the value of maxing out Pokémon Storage for 99.999% of players.

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**Updates:**

* In June 2017, max capacity for items [was increased to 1500][1].
* In May 2018, max capacity for items [was increased to 2000][2].


  [1]: https://twitter.com/PokemonGoApp/status/878038226191233028
  [2]: https://twitter.com/PokemonGoApp/status/996480700877504512
  [3]: https://i.sstatic.net/X8gUI.jpg