Full-Stack Developer Tax Guide

A developer who handles both frontend and backend to build the entire service. Guidance tailored to your field, from income structure to expense processing and tax-saving points.

You handle frontend and backend solo — let us handle your income filing in a single pass too

한국어 · 日本語 · 中文

I'm taking on several MVP outsourcing projects solo — at what revenue level do I need to register a business?

It depends on your revenue scale and how ongoing the work is, but if you're taking on outsourcing work continuously and repeatedly, business registration is the standard approach — continuing to receive everything as a 3.3% freelancer without registering can later be flagged as unreported revenue. Some developers run several outsourcing projects solo, cross the simplified-taxation threshold without noticing, and get forced into general taxation the following year, missing out on input VAT credits they could have claimed along the way — so we recommend reviewing your revenue trend in advance and designing your conversion timing ahead of time.

Income Structure Features for Full-Stack Developers

A high proportion work as solo developers or co-founders at early-stage startups
Lump-sum outsourcing contracts for full builds (websites, MVPs) are common
Using AI tools to run several projects solo, which speeds up revenue growth

Key Necessary Expense Items

Frontend and backend tool subscriptions overall (Figma, cloud servers, DBs, etc.)
No-code/low-code platform fees (Bubble, Webflow)
Stamp tax and e-contract service costs for outsourcing MVP development contracts
AI coding tool subscriptions — Cursor, Copilot, ChatGPT
Depreciation on work laptops and server equipment

Tax Advantages for Full-Stack Developers

Optimizing tax benefits for solo founders

We review the youth startup tax reduction alongside venture business certification to design a structure that lowers both corporate and income tax.

Managing taxation type for MVP outsourcing revenue

We design the timing to convert between simplified and general taxation ahead of your revenue trend.

Designing co-founder equity structure

When several full-stack developers co-found together, structuring dividends and salary by equity share can produce real tax savings.

The Most Common Mistake in the Field

Some developers run several outsourcing projects solo, cross the simplified-taxation threshold without noticing, and get forced into general taxation the following year, missing out on input VAT credits they could have claimed along the way.

A Must-Check for On-Site Freelancers — Disguised Subcontracting & Employee Status

Even if your contract says freelancer, you may be judged an employee based on your actual working reality

A work reality resembling employment carries disguised-subcontracting risk

If you work on-site at a startup or SI firm with fixed working hours, direct work direction and attendance management from the client, and use of the in-house development environment, your actual status may be judged as an employee even if your contract says freelancer. If disguised subcontracting is found, it can lead to retroactive four-major-insurance enrollment and back taxes on employment income.

Work autonomy needs to be preserved to stay safe

A structure where you contract based on scope of work and deliverables, and can decide your own detailed working methods and hours, keeps a freelance (business income) contract safe.

Frequently Asked Questions

Different Roles, Same Tax Troubleshooter: Tax103

Consult with Tax Accountant Kwon Ji-hyun, who understands the income structure and expense items unique to full-stack developers

카카오톡 문의 상담 예약