Sole Proprietor vs. Partnership: The Basic Difference

Neither a sole proprietorship nor a partnership is taxed as a separate legal entity the way a company is. In both cases, the business profit ultimately flows through to individuals and is taxed at personal progressive rates. But the mechanics of how that happens — and who files what — differ.

Sole Proprietor Tax

As a sole proprietor, your business is not legally separate from you. Your business profit (revenue minus allowable expenses) is simply added to any other personal income you have and taxed together at the standard progressive individual rates: 0% up to LKR 1,800,000, then 6% through 36% on each successive slab.

You file one personal income tax return covering all your income sources. If your estimated annual tax exceeds LKR 6,000, quarterly SET instalments apply.

Partnership Tax

A partnership itself is generally not taxed as a separate entity for income tax purposes — but it does have its own filing obligations. Key points:

• The partnership must file an annual partnership return declaring total partnership income and how it was divided among partners
• Each partner then declares their individual share of partnership profit on their own personal tax return
• Each partner’s share is taxed at their own individual progressive rate — so two partners with very different total incomes can pay very different effective tax rates on the same partnership
• Partners are individually responsible for their own quarterly SET instalments on their share of expected partnership profit

Deductible Expenses (Both Structures)

Ordinary business expenses — rent, salaries paid to staff (not partners’ own drawings), utilities, stock, marketing, professional fees — are deductible before profit is calculated, in both a sole proprietorship and a partnership.

Which Structure Should You Choose?

This depends heavily on how many people are involved, how profit will be split, and your growth plans. A sole proprietorship is simpler to administer with one owner. A partnership formalises profit-sharing between multiple people but adds a layer of filing complexity. Neither offers the liability protection of a registered company, which is a separate consideration beyond tax.

Common Mistakes

• Partners not declaring their individual share on their personal return, assuming “the partnership already paid”
• Sole proprietors mixing personal and business expenses, making it hard to substantiate deductions
• Missing quarterly SET instalments on business profit

Calculate Your Tax

Use our free Income Tax Calculator and Quarterly SET Calculator to estimate your liability.