Contractors vs full-time engineers for startups

Hire a contractor when the work has an end date and a full-time engineer when the work is the company. A contractor is the right call for a defined build (a migration, a prototype, a fixed integration) or to cover a gap until you can run a real search. A full-time engineer is the right call when you need someone who carries context for years, owns the codebase, and is bought in through equity. Most early-stage mistakes come from using one where you needed the other: contracting out your core product, or full-timing a six-week job.

This post is the cost math, the IP and classification basics, and a clean way to convert a contractor you love into a full-time hire. It is not legal or tax advice. For where contractors fit against your first permanent hires, see first engineering hires after a seed round and how many engineers should a startup hire.

When does a contractor actually make sense?

Three situations where contract or fractional beats a full-time hire:

• The work is scoped and finite. A data migration, a one-off integration, a design-partner prototype. You can describe the deliverable and the done state in a sentence. Hiring a permanent engineer for a six-week job means you own a salary after the job ends.
• You need a senior skill part-time. A fractional staff engineer or fractional CTO two days a week can set architecture, run interviews, and unblock a junior team for a fraction of a full salary. This is common pre-seed and right after a seed round when you cannot yet justify a full-time staff hire.
• You are bridging a gap. A strong search for a senior engineer takes weeks. A contractor keeps the roadmap moving while you run it, instead of pressuring you into a rushed permanent hire you will regret.

When does it not make sense? When the work is your core product and never ends. The engineer who builds your main codebase should be bought in for the long run, which means equity and a real stake. A contractor has no reason to care about the thing you are building in two years, and the context they accumulate walks out the door when the invoice stops. Founding-level work in particular should be full-time: see what a founding engineer actually does.

What does a contractor really cost versus an employee?

The sticker shock is real: a senior contractor in SF or NYC often bills $150 to $250 an hour, which looks like $300,000-plus a year. But you are not comparing hourly rate to salary. You are comparing the full loaded cost of an employee to the full cost of a contractor for the actual hours you need.

An employee costs more than their salary. Add payroll taxes, benefits, equipment, software, and overhead, and the loaded cost is usually 1.2 to 1.4 times base. A contractor invoices their rate and that is the bill. No benefits, no payroll tax on your side, no equity, and you can end the engagement when the work ends.

The table shows the whole point. For a full year of continuous work, a contractor is far more expensive than an employee, and you get no equity alignment. For a 10-week scoped build, hiring a full-timer makes no sense: you would carry a $237,500-a-year cost for a job that is done in March. Match the instrument to the duration. For where the salary figure comes from, see senior software engineer salary in SF and NYC for 2026.

What about equity, IP, and worker classification?

Three things founders get wrong, in order of how much they can hurt you later.

IP assignment is not automatic

This is the one that can blow up a diligence round. For an employee, work created on the job generally belongs to the company, and your offer letter should still include an explicit IP and invention-assignment agreement. For a contractor, the default is the opposite in important cases: absent a written assignment, the contractor can retain rights to what they built. Every contractor must sign an agreement that assigns all work product to the company and includes confidentiality, before they write a line of code. Acquirers and investors check this. Missing contractor IP assignments are a classic reason a deal stalls. Not legal advice: have a lawyer paper this.

Classification has rules

You do not get to call someone a contractor just because it is cheaper. US and state rules (the IRS factors, and stricter state tests like California's ABC test) look at control: who sets the hours, who provides the tools, whether the person works only for you, how integrated they are into the team. A full-time, long-term, you-direct-their-day engineer is an employee in substance even if you pay them on a 1099. Misclassification means back taxes, penalties, and benefits exposure. The cleaner the contract engagement (scoped deliverable, their tools, their schedule, finite term), the safer the classification. Not legal advice.

Equity is for the long haul

Contractors are paid in cash, not equity, in almost every case. Equity is how you align someone with the company over a four-year vest, and a contractor has no four-year relationship with you. If you find yourself wanting to give a contractor meaningful equity, that is a strong signal they should be a full-time hire instead. For how to size grants when you do convert, see how much equity a startup engineer gets by stage.

How do you convert a great contractor into a full-time hire?

The best outcome of a contract engagement is finding someone you want to keep. A contract-to-hire path lets both sides try before committing, which is why it works so well. Here is a clean way to run it:

1. 01Be honest up front. If conversion is possible, say so at the start. "This is a 10-week build, and if it goes well we would love to talk about full-time." That sets the right expectations and lets you both evaluate fit during the work.
2. 02Treat the contract as the interview. You are watching how they scope, communicate, and ship. This is better signal than any take-home assignment because it is the real job.
3. 03Make the offer concrete and quick. When the work is done and you both want it, move fast. A vague "we should make this permanent someday" loses people. Put a real number and a real equity grant in front of them. Our guide on how to close an engineering candidate applies here.
4. 04Expect a comp reset. Their contract rate is not their salary. A full-time offer trades the higher hourly rate for a lower base plus equity, benefits, and stability. Frame it as that trade, not a pay cut.
5. 05Paper the transition. New employment agreement, fresh IP assignment as an employee, equity grant, and a clean end to the contractor relationship. Not legal advice: have your lawyer handle the handoff so there is no gap in IP ownership.

One caution: do not run a permanent role as a perpetual contract to avoid the commitment. Strong engineers read that as a lack of conviction, and the classification risk grows the longer it runs. If you have decided the work is permanent, hire for it. For how that hire fits a fresh raise, see hiring senior engineers after a raise.