Assets is not the correct figure to look at
For a charity, the number you need to look at is "free reserves", which isn't a number on the balance sheet, but may be in the Trustee's report, or you can work it out yourself.
Assets that the charity needs in order to carry out its activities, such as the servers the site is hosted on are not free reserves. The cash is, provided it isn't restricted funds, but you need to deduct the liabilities and commitments from that.
 Commitments are also not shown on the balance sheet, but should be in the notes to the accounts somewhere. Where you have a contract with someone to provide services, and the money isn't due yet, because the service has not yet been provided, that is a commitment.