Systems Architect Tax Guide

Q: I provide technical advisory to several companies — is business registration advantageous for me?

If your revenue scale is large and you have significant related expenses (office space, equipment, etc.), registering a business and claiming input VAT credits as a general taxpayer can be advantageous.

Q: My advisory fees are clustered in a single year and I expect a large tax bill — is there anything I can do?

You can review spreading out your contract or payment schedule, or using income-deduction products like the Nolan Umbrella Fund and pension savings.

I visit several companies for technical advisory work — how much can I claim in vehicle maintenance costs?

If your advisory revenue from visiting multiple companies grows large enough to make you a double-entry bookkeeping obligor, the special rules for business-use vehicles apply — depreciation (including lease/rental payments) is capped at 8 million KRW a year, and the overall cap including fuel and insurance is 15 million KRW a year. Keeping a careful driving log lets you claim the business-use portion with no cap, and since business costs can be fully disallowed if you're not carrying business-use-only auto insurance, we recommend checking your enrollment status first.

Income Structure Features for Systems Architects

A high-value role where senior freelance and technical-advisory contracts are common

Providing advisory and design services to multiple companies simultaneously is common

Executive-level stock option contracts, like startup CTO roles, are also common

Key Necessary Expense Items

Architecture design and documentation tool subscriptions

Technical conference and seminar registration fees, plus presentation material production costs

Shared-office rent for handling multiple clients

E-contract and legal consulting costs related to technical advisory contracts

Vehicle maintenance costs (depreciation, fuel, insurance) for visiting multiple companies

Tax Advantages for Systems Architects

Spreading out high-value advisory income timing

We spread out contract and payment timing to avoid clustering income in a single year and to ease the progressive rate burden.

Maximizing input VAT credits when advising multiple companies

We claim input VAT credits on related expenses like office space and equipment through business registration.

Tax planning for CTO-level stock options and incentives

We coordinate the timing of exercise and receipt to manage your tax burden.

The Most Common Mistake in the Field

Some people provide technical advisory to several companies and end up receiving high advisory fees clustered into a single year, pushing them into the top comprehensive income tax bracket and resulting in far more tax than expected.

Frequently Asked Questions

I provide technical advisory to several companies — is business registration advantageous for me?

My advisory fees are clustered in a single year and I expect a large tax bill — is there anything I can do?

I drive to visit several companies — how much of my vehicle purchase and maintenance costs can I claim as an expense?

If your advisory revenue is large enough to make you a double-entry bookkeeping obligor, the special rules for business-use vehicles apply. Depreciation (including lease/rental payments) is capped at 8 million KRW a year, and the overall cap including fuel and insurance is 15 million KRW a year — keeping a driving log lets you claim the business-use portion with no cap. You also need to check whether you're carrying business-use-only auto insurance, since without it, related costs can be fully disallowed.

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