I would
assume you only pay taxes on the earnings that have actually been paid out to you. I would equate it to me making a contract with my clients that says they pay me $500 (received), but are guaranteed to pay me another $500 in 30 days (not received). I only pay taxes for that month on the $500 I received.
It's a bit late now, but what you should be doing moving forward is paying estimated taxes. As it suggests, you calculate the taxes you should owe on your income that doesn't automatically have taxes deducted, pay the taxes manually, then at the end of the year you should find all your tax obligations are settled. Note there is some sort of penalty I believe if your calculations aren't accurate and you underpay by like...$1000 at least I believe.
Normally, these are paid quarterly, but you could pay them monthly as well to make the payments more manageable so you can budget more easily.
The IRS has all the info you will need on estimated taxes: http://www.irs.gov/Businesses/Small-Businesses-&-Self-Employed/Estimated-Taxes
Form 1040-ES is the form you'll use to calculate the taxes you owe.
However, since the year is over, and if you intend to pay taxes on that $5000, you'd likely just want to fill out your tax return, report the earnings, and see how much you owe (or how much it deducts from your refund).
Slightly off-topic: If you're pushing $16,000 worth of earnings through Adwork, why have they only sent you $5000? They are net-30 with a $35 minimum payout, so you should certainly have all your funds by now unless you made the last $11,000 in the last month? And if it was in the last month, then at that commission level, you should ask for net-15 or net-7.
OP where do you live in America, thats two continents.
I don't have to look at it, only the citizens of USA call their country America.
Then why did you even ask in the first place...?
