How to Change Your Sole Proprietorship to an LLC

A client's accounts payable portal rejected our W-9 twice a month after the sole proprietorship became an LLC, and the portal was not broken. The form carried the LLC's name on line 1 and the LLC's new EIN underneath it, which is the obvious way to fill it in and, for a single-member LLC that had not elected corporate treatment, the wrong one.

That is one form out of a stack. The state filing created a company inside one record at one office. The bank, the IRS, the licensing counter, the insurer, the payment processor and every client's vendor file still hold the name of a person, and each of them changes on its own paperwork, at its own speed, and only when asked.

Which is the whole problem: the formation is finished and nothing downstream knows it happened. What follows is the order those records move in, and which of them are governed by a rule you can look up rather than by somebody's internal policy - because the two behave very differently when you push on them.

The filing date is a line, not a switch

The state created a legal person and recorded the moment it started existing. Delaware writes the mechanism in one sentence: an LLC "is formed at the time of the filing of the initial certificate of formation in the office of the Secretary of State or at any later date or time specified in the certificate," and from then on it "shall be a separate legal entity" (6 Del. C. § 18-201, read 19 August 2026). Your state's act says the same in its own words. If you asked for a delayed effective date, the date on the stamp is not the date that counts.

Everything dated before that line was done by you: the lease, the merchant account, the insurance policy, the license, the signed statement of work. None of it moves because you started typing LLC after your business name.

One thing did appear that you never had as a sole proprietor. A registered agent and a registered office, on public record, now the address where anything official goes. If a formation service filled that slot with itself on a bundled first year, decide early rather than in month eleven whether you want that job back in your own hands.

The EIN answer is not the one you were sold

Formation services sell an EIN as a mandatory add-on. The IRS is less certain about it than they are.

Its page on when to get a new EIN gives sole proprietors three triggers: you incorporate, you form a partnership, you declare bankruptcy. Forming an LLC is not among them, and the same page confirms it from the other side. Under limited liability company, it lists among the situations where you do not need one: "Use your sole proprietor EIN for your single-member LLC and don't choose to be taxed as a corporation or an S corporation and don't have employees or owe excise tax" (IRS, When to get a new EIN, page last reviewed 21 July 2026).

The other direction is where the requirement bites. For employment tax and certain excise taxes a single-member LLC counts as a separate entity even while it is disregarded for income tax, and the IRS states that for wages paid after 1 January 2009 the LLC "is required to use its name and employer identification number (EIN) for reporting and payment of employment taxes" (IRS, Single member limited liability companies, read 19 August 2026, citing T.D. 9356). The same page says most new single-member LLCs classified as disregarded entities will need to obtain an EIN, and that one with no employees and no excise tax liability does not need one - but can apply for one anyway if it needs a number to open a bank account, or if state tax law requires the LLC to have one.

So: if you will ever run payroll, get it now and stop thinking about it. If you will not, you may still want one, because state portals and bank applications ask for a number attached to the entity name.

Line 1 of the W-9 is where a disregarded entity trips

Why the rejected form was wrong is set out in the IRS's own instructions to the people who collect these. The instructions for the requester of Form W-9 say that "for proper processing, information for disregarded entities is reported as the owner's name on line 1, and the disregarded entity's name is entered on line 2," and that an LLC which is a disregarded entity fills in line 3a by checking the box "for the tax classification of its owner" (Instructions for the Requester of Form W-9, Rev. March 2024, read 19 August 2026).

The single-member LLC page says the same about the number: such an LLC "generally must use the owner's social security number (SSN) or employer identification number (EIN)," and the W-9 "should provide the owner's SSN or EIN, not the LLC's EIN."

Individual on line 1. LLC on line 2. Owner's number. It reads backwards and it is what the form asks for. If you elected corporate or partnership treatment the answers change, so confirm your election before a stack of corrected forms goes out.

Your bank wants beneficial ownership even though FinCEN stopped

Two rules that sound identical and are not. The first one moved twice, and most write-ups carry only the second move.

U.S. companies stopped being reporting companies on 26 March 2025, when FinCEN published an interim final rule that narrowed the definition of reporting company. The final rule made that permanent: FinCEN issued it on 11 August 2026, it appeared at 91 FR 52508 and took effect on 14 August 2026, and Treasury describes it as adopting "the exemptions set out in the interim final rule issued in March 2025, making the rollback of beneficial ownership reporting by U.S. companies permanent" (Treasury, 11 August 2026). FinCEN's own alert is blunter: "U.S. companies are exempt from BOI reporting requirements and therefore, are no longer required to file BOI reports" (FinCEN, Beneficial Ownership Information Reporting, alert updated 11 August 2026, read 19 August 2026).

You can see the result in the regulation itself. The definition of reporting company now has one live limb - an entity formed under the law of a foreign country that has registered to do business in a State or tribal jurisdiction - and the paragraph that used to cover domestic companies stands as [Reserved] (31 CFR § 1010.380, amended at 91 FR 52528, 14 August 2026). So a checklist telling you to file a BOI report within 30 days of forming your LLC is not merely out of date this month. It has been wrong for U.S.-formed companies since March 2025.

Your bank is not applying that rule. It is applying the customer due diligence rule, a different section of the same chapter, which requires a covered financial institution to identify the beneficial owners of a legal entity customer "at the time a new account is opened," either by obtaining the certification at appendix A to the section or by collecting the same information another way (31 CFR § 1010.230, last amended 2017, read 19 August 2026). That rule sits outside the Corporate Transparency Act reporting regime, and it did not move when the reporting regime did.

FinCEN has eased it, in the direction that does not help you here. An order of 13 February 2026 lets a covered institution stop repeating the exercise every time a legal entity customer it already has opens another account: identification can be limited to when that customer "first opens an account," to any later point where something calls the information already held into question, and to whatever the institution's risk-based procedures require (FIN-2026-R001, exceptive relief order, issued 13 February 2026). Your LLC is at the first of those three. It is a new customer on day one, whatever the bank already knows about you.

What the appointment wants: the filed formation document with the state's stamp, the EIN assignment notice if you obtained one, photo ID for each beneficial owner, and that certification. Bring the operating agreement too - some banks want it, and a second appointment costs another week.

Licenses get issued again, not converted

This is the tier people underestimate. Washington states the mechanism most plainly:

The process to change a business structure (for example, change from a sole proprietorship to a corporation) is the same as starting a new business.

That page goes on to say you submit a new Business License Application, that "you will be given a new Unified Business Identifier (UBI) number," and that "you will probably need to re-apply for all of the licenses you currently have," using a contractor's license from a separate department as its example (Washington Department of Revenue, Change your business structure, read 19 August 2026).

Not every state words it that way, but the logic travels: the applicant on the old license is a person, and the applicant now is a company. Assume re-application, and put the question in those terms - does this license follow a change of legal entity, or do I file a new application? A handful of states also hang a step off the formation itself rather than off any of your accounts, New York's newspaper publication requirement for new LLCs being the one people have heard of, and that kind of rule lives on your Secretary of State's own page rather than at any counter in this section.

Sales tax registration earns its own calendar line, for lead time rather than difficulty. Whether your state wants a fresh permit in the LLC's name or will move the existing one is a question for that state's revenue agency and nobody else. Either answer costs time you do not control: Texas tells new permit applicants to "allow 2-3 weeks to receive your permit" (Texas Comptroller, Texas Online Tax Registration Application, read 19 August 2026). Starting that in week one rather than week four is the difference between a gap and no gap, and if a new permit is what you end up with, do not surrender the old registration until the new one has issued.

Trade names are the quiet one. A DBA is a name registered against a registrant, and the registrant on yours is a person. Whether the LLC inherits that registration or has to file its own belongs to whichever office holds the register - a county clerk in some states, a state agency in others - so ask there rather than assuming the name travels with the business.

The accounts that never send a notice

The bank and the state send paperwork that reminds you they exist. These do not. Nothing in this group is set by a statute you can cite, either - each one is a private counterparty applying its own onboarding rules, which is why the answer here is a phone call rather than a regulation:

• Insurance. The named insured on a policy issued to you personally is you. Ask the carrier to reissue with the LLC named, then circulate a fresh certificate, because onboarding portals compare it against the contract.
• Payment processor and merchant account. Underwriting was done on a sole proprietorship. A change of legal entity commonly means a fresh application rather than an edit, and the processor decides which.
• Payroll service, EFTPS, and state employer accounts. A new EIN means new enrollments at each. State withholding and unemployment accounts are separate again, and separate from the license.
• Retirement plan. A solo plan adopted by a sole proprietorship names that sponsor in the plan documents. Ask the administrator what a change of sponsor takes.

Vendor accounts, the domain registrar, subscriptions and equipment finance are low stakes taken one at a time, which is exactly why a personal name can sit in them for years. So is your signature block, and that one is worth changing the same afternoon: sign as a member or manager of the company rather than as yourself. It is a small habit and it is the habit the separation rests on.

Contracts already running are the exception. Moving one to the LLC is an assignment or a novation, and the other side has to agree in writing. For a lease, a loan, or anything carrying a personal guarantee, get advice first.

Sequencing, because half of these depend on each other

Order matters more than speed, because half of these will not process at all until something else has issued:

1. Week 1. Filed document in hand, then the EIN, then the bank appointment. Almost nothing further works without those two documents.
2. Weeks 1-2. Sales tax registration first because it has the longest queue, then the state or city license application.
3. Week 2. Insurance reissued, new W-9s out to every client who pays on invoice.
4. Weeks 3-4. Processor, payroll, vendor accounts, registrar, signature blocks.
5. Once each replacement has issued. Surrender the old registrations and close the personal account. Last, not first, because checks made out to the old name keep arriving for months.

Then comes the part that exists only because you own an entity now: recurring state filings, and a status the state tracks whether or not you look at it. The first report is often due sooner than you would guess. Find out today what your state's record says about you and how to read it, because a delinquency notice is mailed to whatever registered office the state has on record, which on a week-old LLC is often a formation service's address rather than yours.

The two records worth opening before any of it

Almost none of the delay in this is work. It is queues at offices that answer at their own pace, which is why the order above matters more than how quickly you move through it. Applying for a city license before the EIN exists means filling that form in twice. Correcting a W-9 before you have settled which name belongs on line 1 means sending it twice.

Two records answer most of what the rest of the list raises. The first is your state's entity page for the LLC: the name, the registered agent, the registered office and the status, as anyone checking you can see them. The second is the vendor record a client holds on you, because a portal that quietly parks an invoice will never say which field it disagrees with, and a name or TIN that does not match is invisible from your side.

One date belongs on the calendar today rather than later. If a formation service holds your registered agent slot on a bundled first year, set a reminder at eleven months. Letting that lapse without a replacement is one of the few ways to undo the whole exercise, and switching without leaving a gap has an order of operations of its own.