You cannot do this legally
General rules
Under US law you are required to file a Form 1099 with the IRS for this payment if it was for a trade or business purpose. ( $1,000.00 is above the current reporting limit of $600.) This you cannot do without the recipient's name (personal or business) and address. You will also need their SSN or TIN. Failure to file the 1099 may be a violation of law.
Private people, as well as businesses, get 1099s which are also filed with the IRS. I myself have received 1099s as a private individual for freelance work. (Corporations mostly do not get 1099s.)
Private individuals as well as businesses report payments on 1099s.
Such a person might be involved in unlawful tax evasion, and the demand for payment in bitcoin might support a reasonable suspicion of this. If so, you might be accused of being an accessory.
If the person is foreign (non-US) and the work was not done in the US it may not need to be reported, but if you do not know the person's location you cannot safely assert that it is outside the US.
If you intend to deduct the payment on your own taxes as a business expense, you may also need to have a receipt showing the recipient of the money.
It would seem that if the payor/client is in the US and the work was done for a trade or business (which includes a non-profit, but not a hobby or personal site) and the amount is $600 or more, there is no safe and legal way to hire a person or firm without knowing the name, address, and (in most cases) TIN (taxpayer identification number) of the contractor, or at least using ones "best efforts" to obtain the TIN. See the various IRS instructions below for details.
IRS Instructions
According to the Form 1099-Misc/1099-NEC insatructions
Report on Form 1099-MISC [or 1099-NEC] only when payments are made in the course of your trade or business. Personal payments are not reportable. You are engaged in a trade or business if you operate for gain or profit. However, nonprofit organizations are considered to be engaged in a trade or business and are subject to these reporting requirements.
Generally, payments to a corporation (including a limited liability company (LLC) that is treated as a C or S corporation) [are not reportable].
If you are required to file Form 1099-MISC, you must furnish a statement to the recipient.
Enter [in Box 3] other income of $600 or more required to be reported on Form 1099-MISC that is not reportable in one of the other boxes on the form.
File Form 1099-NEC, Nonemployee Compensation (NEC), for each person in the course of your business to whom you have paid the following during the year:
At least $600 in ... Services performed by someone who is not your employee (including parts and materials) (box 1);
Generally, you must report payments to independent contractors on Form 1099-NEC in box 1.
If the following four conditions are met, you must generally report a payment as NEC.
- You made the payment to someone who is not your employee.
- You made the payment for services in the course of your trade or business (including government agencies and nonprofit organizations).
- You made the payment to an individual, partnership, estate, or, in some cases, a corporation;
- You made payments to the payee of at least $600 during the year.
Instructions for Form 1042-S specify that one must report for foreign payees:
Compensation for independent personal services performed in the United States.
General Instructions for Certain Information Returns says:
Recipient names.
Show the full name and address in the section provided on the information return. If payments have been made to more than one recipient or the account is in more than one name, show on the first name line the name of the recipient whose TIN is first shown on the return.
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TINs.
TINs are used to associate and verify amounts you report to the IRS with corresponding amounts on tax returns. Therefore, it is important that you report correct names, social security numbers (SSNs), individual taxpayer identification numbers (ITINs), employer identification numbers (EINs), or adoption taxpayer identification numbers (ATINs) for recipients on the forms sent to the IRS.