US tax return 2025 Free potential analysis

30 articles

Your US company, its taxes and every deadline under control.

A US company with a permanent establishment pays tax in the US, and its owners pay tax at home too. In between sit forms like 1120, 1065 and 5472, federal and state taxes, payroll, sales tax and withholding tax. Mount Bonnell Advisors handles all of it for your company and speaks the language of both tax systems.

Here you'll find our guides on taxing US companies: what's due, when it's due and how to avoid costly mistakes.

All guides on US taxes for companies

US taxes for companies: federal, state and home country The returns, reports and deadlines a US LLC or corporation with European owners faces, in one overview with a calendar. Read more → Understanding the IRS W-8 forms Which of the five W-8 forms you need, who gets it and how long it is valid. Read more → America taxes differently. Mostly in your favor. Income tax, social security, capital gains, estate tax, corporate tax and sales tax: the US tax system at a glance. Read more → How the IRS thinks and works How the IRS audits, what it looks for and how to deal with it as a business owner, from first-hand experience in the US. Read more → State-by-state guide to nexus laws for US sales tax The nexus thresholds of every sales tax state in one table, with the latest changes. Read more → How your home country taxes your US company Tax treaties, reporting duties, entity classification, substance and active income: how your country of residence views your US company. Read more → Taking money out of your US company tax-efficiently A loan from your own company or a salary as managing director: how to take money out of your US company. Read more → How business profits are taxed in the US Which taxes apply to the profits of your LLC, C Corporation or LP, in three guides. Read more → Payroll in the US Payroll in the US: income tax, FICA, unemployment insurance, forms and deadlines for employers. Read more → Sales tax in the US How sales tax works, when nexus arises, what is taxable and when you have to remit. Read more → BE-13 report to the BEA: due 45 days after formation When your US company files the BE-13 within 45 days, which form applies and which BEA reports follow later. Read more → Delaware franchise tax: $400 for the LLC, every year on June 1 The Delaware LLC annual tax, the corporation's annual report and franchise tax, the two calculation methods, deadlines and penalties. Read more → Getting an EIN without an SSN: fax, phone, mail and Form SS-4 How to get an EIN for your LLC or corporation without an SSN: SS-4 line by line, fax, phone, mail and timing. Read more → Form 1065 and K-1: the LLC with members from Europe Form 1065, Schedules K-1, K-2 and K-3, the March deadline and Section 1446 withholding for foreign members. Read more → Form 1120 for your corporation: every year, even without a profit Who files Form 1120, by when, what goes in it and what filing late costs, for the Inc. and the LLC taxed as a corporation. Read more → Missed Form 5472? The $25,000 penalty and how to get it waived The penalty for a missing Form 5472, how it arises, the routes to relief and what the request needs. Read more → Filling in Form 5472: your single-member LLC's report, part by part The report of a foreign-owned single-member LLC, explained field by field, with cover sheet, deadlines and filing. Read more → Glossary of US business taxes: from EIN to franchise tax Every US business tax term explained in a sentence or two, with a link to the page that goes deeper. Read more → Got a letter from the IRS? What it means and which deadline applies The most common IRS letters to businesses and individuals, what they mean, which deadline applies and how to respond. Read more → Your US LLC's annual obligations: the calendar for the whole year Which returns, reports and filings your US company owes each year, to whom and by when, on one page. Read more → Sales tax nexus by state: the thresholds for all 50 states and DC The revenue or number of sales at which each state requires you to collect sales tax, in one table with a source for every state. Read more → US sales tax: when a state turns you into its tax collector When a state wants sales tax from you as a seller from Europe, what the marketplace handles for you and what it doesn't, and how registration and filings work. Read more → US LLC bookkeeping: which records the IRS wants to see, and for how long Which records your US LLC must keep, what Form 5472 also requires, how to convert foreign currency and how long to keep your records. Read more → US LLC tax return: which form your LLC files with the IRS Which federal and state return your LLC files, depending on whether it's treated as a single-member LLC, a partnership or a corporation. Read more → US tax ID numbers: EIN, ITIN or SSN, which one you need EIN, ITIN, SSN and TIN: what each number is, who issues it, who needs it and which one goes on which US form. Read more → W-8BEN: a guide for freelancers and individuals The W-8BEN line by line: who fills it in, what freelancers enter in Part II, which treaty article applies and how long the form stays valid. Read more →

What we take care of for you

All services and fees →
Corporation tax returnForm 1120 and Form 5472 for your US corporation.View service →LLC and LP tax returnForm 1065 and K-1 for your LLC or LP.View service →EIN applicationYour company's US tax ID, applied for by us.View service →PayrollPayroll, payroll taxes and filings for your employees in the US.View service →Sales TaxRegistration and returns in the states where you have nexus.View service →IRS letters and penaltiesMail from the IRS? We respond, request relief and set things right.View service →Withholding TaxW-8 forms, withholding and treaty benefits, done right.View service →
Sebastian Sauerborn
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Sebastian Sauerborn

Sebastian Sauerborn is the founder of Mount Bonnell Advisors in Austin, Texas. He moved from London to the United States in 2008, spent years living on his own ranch in Bastrop County, and for more than twenty years has guided European entrepreneurs and families as they make the leap. He knows the questions you have right now not just from client files, but from his own life.

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