An interesting thing: JustGiving removed their mandatory 'platform fee' last year, so a donation to Captain Tom's cause does not include a fee, BUT there is an 'optional contribution' box as part of the process.

That makes sense - they're a business, and incur lots of costs.

Here's the default donation amount, if you click through to donate. A couple of things to note there:
- The donation amounts are set as buttons.
- The 'optional contribution' to JustGiving is a dropdown, rather than buttons.
- The 'optional contribution' is set to 10% by default.

Because it's a dropown, you have to click at least twice to change the % you give to JustGiving.

(Because the main donation is set as buttons, you only have to click once to change it. ie, it's harder to change the amount you give to JustGiving)

The contribution to JustGiving is optional, but if you wanted to change it to £0, you'd actually have to click 'Other' first.

If you click 'Other', you're presented with this screen, where you have to type in an amount.

(Actually you *could* just click 'Continue' now if you wanted to, but the value field is greyed out, so it looks like you have to enter something.)

*If* you try to enter '0' in this box, you actually can't. It just doesn't let you type it. So it *feels* like you have to enter something.

Ie: It's optional, but the UX is set up to make it harder for you to reduce the pre-defined default they've set (10%).

As you have to proactively choose to change the amount, and the UX is set up so that it's difficult to set it to '0' without some mental perseverance, I'd expect the high majority give a contribution to JustGiving alongside the donation to Tom.

If every donor has left the default option, JustGiving will have raised more than £910,000 for themselves, in addition to the £9.1 million going to the NHS.

In other words, the total people have given through this would already be greater than £10 million.

JustGiving also charge a payment processing fee of 1.9% + 20p per donation.

That would mean, from £9.1million, with 45,6992 donors so far to Tom, £172,900 (1.9%) + £91,398.

So the amount that would reach Tom's causes from £9.1m would actually be deducted to £8.835 million.

(a note here - I don't know if they charge the processing fee on the 'charity donation', or whether they charge it on the 'charity donation + justgiving donation'. It's not clear from their fees page. It's worded ambiguously on their site. I've assumed the lower amount)

And of course, you can top up with GiftAid if you like. If you do that, the Government put in 25%. So - if everyone did it (which they won't, and aren't all eligible) - the government would chip in an extra £2.28 million on top of the £9.1 million raised so far.

BUT: JustGiving charge a processing fee on GiftAid claims, of 5%. So they'd take about £114k from the GiftAid amount too.

So, in summary, if everyone leaves the default 'extra' contribution, & claims GiftAid, JustGiving themselves would so far have made around £1million so far.

This is all my maths, so I'm very open to clarification from anyone reading this, or from JustGiving, but I thought I'd share.

I don't begrudge them the above at all, and happily donated adding a contribution to them & adding GiftAid despite knowing this.

But, I think it's worth knowing it, especially as if you ask, the default reply is simply that they no longer have platform fees.