I have simultaneous maintenance contracts with several client companies — do I file separately per company?
You combine the withholding (3.3%) from every contracting company and file it under a single comprehensive income tax return — even with multiple places of business (contracting companies), the filing is consolidated. Some people rely solely on the 3.3% withholding and never reflect real costs like transportation and equipment when filing comprehensive income tax, ending up with an unnecessarily heavy tax burden, so we recommend claiming every real expense — such as travel costs between client sites and configuration-management tool licenses — without missing any.
Income Structure Features for Maintenance Developers
Key Necessary Expense Items
Tax Advantages for Maintenance Developers
Optimizing income classification across multiple contracts
When you contract with several clients at once, we judge the actual nature of your income as business or employment income to adjust your tax burden.
Saving on taxes by allocating vehicle costs given frequent travel
Given how often this role visits client sites, we allocate vehicle-related expenses by business-use ratio and reflect them.
Managing irregular income with the Nolan Umbrella Fund
You can use it as a cushion for income that fluctuates with contract end and renewal timing.
The Most Common Mistake in the Field
Many people with simultaneous maintenance contracts at several SI firms rely solely on the 3.3% withholding and never reflect real costs like transportation and equipment when filing comprehensive income tax, ending up with an unnecessarily heavy tax burden.
Frequently Asked Questions
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