This no longer works! Steam has changed the way that they add funds to your wallet, so this form will no longer work. You can still add a custom amount, however:

Go to the add funds page and decide how much you want to add to your Wallet. Then multiply that amount by 100. Then type this in your address bar:
javascript:submitAddFunds(amount)
For example, if I wanted to add $20.00, I would use:
javascript:submitAddFunds(2000)




This allows you to add a custom amount of funds to your Steam wallet. The minimum amount to add is $5.

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