The General Rule: Where the Work Is Performed
The default rule: you owe state income tax to (a) your state of residence on your worldwide income, and (b) any state where you physically performed work, on income earned while in that state.
For remote freelancers serving clients in multiple states: if you performed all your work from home in Texas (no income tax), Texas is your only state nexus. The clients' locations don't typically create state tax obligation — you owe state tax based on YOUR location, not the client's.
Travel for client work: physical presence in another state creates nexus there. If you fly to California for a 3-day client meeting, those 3 days of work might be sourced to California. Most states have de minimis exceptions (less than 60 days, or less than $20K of in-state income, etc.) but this varies.
Concrete example: Texas-based consultant, $200K of revenue. 5 days traveling to California for client work, performing about $4K of work during that time. California claims tax on the $4K performed in California — even though the consultant lives in Texas with no California ties otherwise. Many freelancers miss this and only file in their home state.
Reciprocity agreements: certain neighboring states (PA-NJ, MD-VA, WI-IL, etc.) allow workers to file only in their home state for wages earned in the other. Reciprocity is mostly for W-2 employees, less applicable to freelancers.
The Convenience of Employer Rule
Six states apply 'convenience of the employer' rules: New York, Pennsylvania, Connecticut, Delaware, Nebraska, Massachusetts. If you're a freelancer or employee working remotely for an employer/client based in one of these states, the employer-state may tax your income — even if you never physically work in that state.
The rule's mechanism: if your remote work is for YOUR convenience (you preferred to work remotely) rather than the client's necessity, the client's state taxes the income. If the client requires the remote arrangement (you perform a function only available remotely, or the client doesn't have facilities where you'd normally work), the rule typically doesn't apply.
Real-world impact: a Tennessee resident freelancer doing software development for a New York-based client. Convenience rule: the New York client could trigger NY state tax on the income. NY rates: 4-10.9% plus NYC city tax up to 3.876%. Combined potential: 4-15% of the income going to NY despite the freelancer never setting foot there.
Defense: documentation of employer/client necessity for remote arrangement. Contracts specifying remote work as a job requirement. Geographic proximity to relevant customers/markets requiring remote location. None of these are bulletproof but they help.
Tax credits: if your home state has income tax, you typically get a credit for taxes paid to other states (avoiding double taxation). But if your home state is no-income-tax (Texas, Florida, etc.), you have nothing to credit against — you simply pay the other state's tax with no offset.
Establishing Nexus in Other States
States define 'nexus' (sufficient connection to the state requiring tax filing) variously: physical presence above a threshold (typical 30-60 days), economic threshold (sales above $500K or other amount), payroll within the state, property within the state, or various other factors.
For freelancers traveling for client work: track days physically present in each state. Most states have de minimis exceptions — usually 14-30 days don't trigger nexus. Beyond that, you may have filing requirements.
Wayfair decision (2018): expanded states' authority to require sales tax collection from remote sellers. While this is sales tax (not income tax), it set the precedent for states aggressively expanding tax jurisdiction over remote workers.
Significant in-state revenue: even without physical presence, some states assert nexus based on dollar threshold. If you have a single client paying you $200K from California, California might assert nexus based on the economic activity. Threshold varies by state.
Practical advice: track every day spent in every state. Track which clients are in which states. Maintain records that could support nexus determinations if challenged.
Source-of-Income Rules
When freelance income IS subject to a non-resident state's tax, how is the amount calculated? States use different sourcing methods.
Days-worked sourcing: income is allocated based on days worked in the state vs. total days worked. So 10 days in California out of 240 working days = $4,167 of California-source income on a $100K total income.
Service income sourcing: where the customer received the benefit. Increasingly used for service businesses. So a Texas freelancer providing services to a California customer might have California-source income equal to the value of services to that customer.
Single sales factor: some states allocate based on the percentage of total revenue from in-state customers. Common for businesses, less so for individual freelancers.
Multistate freelancers may face overlapping sourcing rules. California uses single sales factor for businesses. New York uses days-worked plus convenience rules. Each state's specific approach matters for calculating exact tax owed.
State Filing Requirements for Freelancers
Resident state: always required. File a resident return reporting all worldwide income.
Non-resident states: required if you have nexus and source income there exceeds the state's filing threshold. Thresholds vary — California requires filing if nonresident income exceeds $5K (2026), some states $1K, some $0.
Multiple non-resident filings: each non-resident state may require its own return. A freelancer with significant work in California, New York, and Illinois might file 4 state returns annually (resident state plus 3 non-resident states).
Cost: tax preparation for multistate freelancers can run $1,500-$5,000+ annually. Many cheaper services don't handle multistate well — paying for competent multistate preparation is usually worth the cost.
Estimated payments: if you'll owe state tax to multiple states, you may need to make state estimated payments. Some states allow combined federal-state estimated payments through their portals; others require separate state-level payments.
Strategic Approaches to Multistate Tax
Strategy 1: maintain residency in a no-income-tax state. Texas, Florida, Tennessee, and other no-tax states don't have a state-level income tax to worry about. Filing in non-resident states (when required) without home-state credits is the only state tax burden.
Strategy 2: minimize physical presence in high-tax states. If your work is location-flexible, avoid traveling to California, New York, etc. for extended periods. Time spent below state nexus thresholds avoids triggering filing requirements.
Strategy 3: contractual structure. Some freelancers structure contracts to minimize convenience-of-employer triggers. Specify the work as 'remote required by client' rather than 'remote for freelancer convenience.' Document the rationale.
Strategy 4: separate sub-businesses for high-state-tax customers. Some freelancers form separate LLCs for in-state work that's taxed there anyway, keeping their main business clean for other states. Adds complexity but can simplify multistate filings.
Strategy 5: stay below state thresholds. If California requires filing for non-residents above $5K, structure your California work to be either zero (avoid) or modest (below threshold). Avoid the $4K-$10K range that triggers filing without significant tax savings.
Strategy 6: quarterly estimated payments to relevant states. If you know you'll owe California tax, make quarterly estimated payments to avoid underpayment penalties. CA requires estimated payments above certain thresholds.