AI agents for business finance: what they can and can't do
What AI agents can do in bookkeeping, close, collections and compliance today, where a person must stay in charge, and how to judge a product.
The short answer
Freelancers in the US who expect to owe $1,000 or more for the year pay estimated tax in four instalments; for 2026 the Form 1040-ES due dates are 15 April, 15 June and 15 September 2026, and 15 January 2027. You avoid the penalty by paying the lesser of 90% of this year's tax or 100% of last year's (110% if last year's AGI was over $150,000). When Nigerian clients pay in lumps, the annualised income instalment method on Form 2210 lets you match payments to when the money arrived.
Why freelancers pay quarterly
A Nigerian client paying your invoice is not withholding US tax for you. The IRS still expects tax to be paid as income is earned, not only in April. Its estimated tax page says individuals, including sole proprietors, generally must make estimated payments if they expect to owe $1,000 or more when they file. The amount covers income tax and self-employment tax, which the IRS sets at 15.3% of net self-employment earnings.
The 2026 dates
| Instalment | Due date (Form 1040-ES 2026) |
|---|---|
| 1 | 15 April 2026 |
| 2 | 15 June 2026 |
| 3 | 15 September 2026 |
| 4 | 15 January 2027 |
The gaps between dates are uneven, two months between the first and second and four between the third and fourth, so plan cash for each one rather than assuming even quarters. Form 1040-ES also says you can skip the January 2027 payment if you file your 2026 return by 1 February 2027 and pay the full balance with it. If a due date falls on a weekend or holiday, paying the next business day counts as on time.
How much: the safe harbours
You avoid the underpayment penalty if your withholding and estimated payments together reach the lesser of:
- 90% of the tax for the current year, or
- 100% of the tax shown on last year's return, rising to 110% if last year's adjusted gross income was more than $150,000 ($75,000 if married filing separately).
For a freelancer whose Nigerian work is new or growing, the prior-year figure is the easy anchor: it is a known number, and paying a quarter of it each instalment protects you from the penalty even if this year turns out bigger. You still owe the full tax when you file; the safe harbour only removes the penalty.
When Nigerian income arrives unevenly
Nigerian clients often pay in clusters: a large milestone after a board approval, nothing for months during budget freezes, a rush before December. Paying four equal instalments can mean paying tax on money you have not yet received. The IRS allows the annualised income instalment method for exactly this case: you work out what you owed based on income actually received in each period and make unequal payments. You show it on Form 2210 when you file, which is also the form that works out whether any penalty is owed.
Worked example (illustrative figures)
Tolu, a single designer in Atlanta, expects $48,000 net from Lagos clients in 2026, with an estimated total federal tax of $10,000. Her 2025 tax was $6,000, so the 100% safe harbour is $1,500 per instalment.
| Period | Received | Equal-instalment plan | Annualised approach |
|---|---|---|---|
| Jan to Mar | $4,000 | $1,500 | Smaller payment, reflecting low income |
| Apr to May | $4,000 | $1,500 | Smaller payment |
| Jun to Aug | $28,000 | $1,500 | Larger payment after the milestone |
| Sep to Dec | $12,000 | $1,500 | Balance of the year |
Paying $1,500 four times ($6,000) meets the prior-year safe harbour, and she pays the remaining $4,000 with her return. The annualised route suits her if she prefers not to pay ahead of income; it takes more paperwork. These are example figures, not a tax calculation.
What goes into the estimate
Form 1040-ES includes a worksheet that builds the figure from your expected income for the year. For a freelancer with Nigerian clients the pieces are:
- Expected net profit: fees from all clients, Nigerian and American, less business expenses such as software, equipment and a share of internet costs.
- Self-employment tax on that profit. For 2026 the form applies the 12.4% Social Security part only up to a wage base of $184,500, and the 2.9% Medicare part on all of it, after multiplying net earnings by 92.35%.
- Income tax after the standard deduction, which Form 1040-ES gives as $16,100 for a single filer in 2026, and after half of the self-employment tax.
- Any credits you expect, including a foreign tax credit if a Nigerian client withholds tax on your fees.
Redo the worksheet when a big contract lands or falls away. An estimate is meant to be revised during the year.
Converting naira before you estimate
Estimates must be in dollars. If a client pays in naira, the IRS says to use the exchange rate prevailing when you receive the income; it has no official rate and its yearly average table has no naira row. Note the rate and source each time money lands. Our guide to converting naira invoices for Schedule C shows how to keep that record.
How to pay
- Online through your IRS account, Direct Pay or the IRS app, which the IRS lists alongside phone and mail.
- By mail with a Form 1040-ES voucher.
- More often than quarterly if it helps: the IRS says weekly, biweekly or monthly payments are fine as long as enough is paid by each due date.
- Check your state too. If your state has an income tax, its revenue department sets its own rules for paying during the year.
Where Pryme fits
A simple habit helps: when a Nigerian payment lands, move a set share aside for tax before you spend. A Pryme account holds USD and NGN, so you can keep naira receipts and the dollar tax reserve in view together and convert with Swap, rate and fee shown first. The Personal Assistant can remind you of each due date. See also self-employment tax on Nigerian income.
Questions people ask
When are 2026 quarterly estimated taxes due?
15 April, 15 June and 15 September 2026, and 15 January 2027, according to the 2026 Form 1040-ES.
Do I have to pay estimated tax on money from Nigerian clients?
If you expect to owe $1,000 or more for the year after withholding and credits, the IRS generally expects estimated payments, whatever country the client is in.
What if a Nigerian client pays me in one big lump?
You can use the annualised income instalment method on Form 2210 to base each payment on income actually received in that period.
How do I avoid the underpayment penalty?
Pay at least the lesser of 90% of this year's tax or 100% of last year's, or 110% if last year's AGI was over $150,000.
Sources
- IRS: Estimated taxes (reviewed 25 Sep 2026) · accessed Oct 2026
- IRS: Form 1040-ES, Estimated Tax for Individuals (2026) · accessed Oct 2026
- IRS: Self-employment tax (Social Security and Medicare taxes) (reviewed 27 Jun 2026) · accessed Oct 2026
- IRS: Foreign currency and currency exchange rates (reviewed 22 May 2026) · accessed Oct 2026
This article is general information, not financial, legal or tax advice. Products described are provided under the terms on this site and are subject to regulation and eligibility.