This question is usually framed as either-or, and that framing is the first thing to fix. An LLC is a legal entity. An S corp is a tax status an LLC can elect. Most marketing consultants who eventually run an S corp are running it inside the LLC they formed years earlier.
LLC first: protection without changing your taxes
Forming a single-member LLC changes your legal position, not your tax return. You still file Schedule C, still pay 15.3% self-employment tax on net profit, still make the same quarterly estimates. What you gain is a liability shield between client work and personal assets, which matters more in marketing than people assume: a campaign accused of infringing a competitor's trademark, a data mishap with a client's customer list, a contract dispute over deliverables. The LLC, kept clean with its own bank account and signed contracts in the company name, keeps those problems at the business's door. Formation is cheap in most states, though a few charge meaningful annual fees or franchise taxes, so check your state's numbers. For most consultants this is a clear early yes, paired with professional liability insurance rather than instead of it.
The Form 2553 election and payroll on consulting profit
The S corp layer exists for one reason: self-employment tax. When your LLC files Form 2553, you become an employee of your own company. You pay yourself a salary through actual payroll, and that salary owes payroll taxes. Remaining profit comes out as distributions, which owe income tax but not the 15.3%. The savings are the payroll tax avoided on the distribution slice.
The costs are real, though: payroll software and filings, a separate Form 1120-S business return with a Schedule K-1, possibly state-level S corp taxes, and less flexibility in how you move money. As a rough shape, consultants with consistent net profit well into five figures beyond a reasonable salary for their work start to see savings that clearly outrun those costs; below that, the election mostly buys paperwork. Model it on your actual numbers before electing, and note the timing rule: the election for a tax year is generally due within two months and fifteen days of the year's start, with late relief available.
Reasonable salary for a solo marketer
The IRS's check on the S corp game is the reasonable compensation requirement. Your salary must reflect what a marketing professional doing your work, at your seniority, for the hours you put in, would be paid. Market salary data for marketing managers and directors, your own past W-2 history, and your billing rates all serve as evidence. A consultant clearing $180,000 who pays themselves a $30,000 salary and takes $150,000 in distributions is waving the exact flag the IRS looks for. Set a defensible number, document how you got it, and revisit it as the practice grows. The honest sequence for most marketing consultants: form the LLC now, run a year or two of real profit numbers, then add the S corp election when the math, not the hype, says it pays.