BOI Capital in Thailand: Minimum Investment and When to Pay

How much capital a BOI project requires depends on the specific activity, rather than a single fixed amount. In practice, four separate requirements need to be considered: the BOI’s minimum investment requirement for the activity, the company’s registered capital, the amount of that capital that must be paid up, and the deadline for paying it up. For the wider requirements beyond capital, see BOI requirements.

The BOI's general minimum investment is 1 million baht per project, excluding the cost of land and working capital, unless the specific activity you're applying under sets a different figure. Most promoted activities carry their own conditions on top of this baseline, so 1 million baht is a floor rather than a number you can rely on for every project.

What counts towards it is broadly the fixed investment in the project itself, such as machinery, equipment and buildings. Land and working capital sit outside the calculation.

Check BOI eligible activities for how to find your activity on the list and its specific conditions before relying on a total.

Minimum investment isn't the same as registered capital. Minimum investment is what the BOI requires you to commit to the project; registered capital is what your company is registered with at the Department of Business Development, a company law concept rather than a BOI one.

A project's minimum investment can sit well above what an ordinary company would need to register as capital, particularly for activities with a high investment threshold. Your registered capital needs to reflect the BOI requirements.

Paid-up capital is the part of that registered capital actually paid in, rather than pledged, and follows the general rules that apply to any company registration in Thailand. See registered capital in Thailand for how registered and paid-up capital work, and what the DBD currently asks you to show as evidence of it. This page covers what's specific to a BOI project on top of that.

The BOI doesn't set one minimum investment for every project. Some activities carry a much higher threshold than the general 1 million baht floor. Others use a different basis for the calculation entirely rather than a lump investment figure, and a small number of knowledge-based activities carry no minimum investment requirement at all.

Software, digital platform and digital content projects, for example, are assessed on annual spend on salaries for the Thai IT personnel the project employs, rather than a one-off investment amount. Manufacturing and other capital-intensive activities can sit well above the general floor, sometimes by a wide margin, depending on the equipment and scale the activity calls for.

The list itself moves. The BOI refreshed its promotion measures for 2026 to 2027 in January 2026, widening incentives for activities such as advanced manufacturing, EVs and R&D. What applied to an activity last year isn't guaranteed to still apply, so check the current announcement rather than an older summary, including this one.

Investment size affects how your application is handled, separate from the minimum figure itself. Larger projects face a longer review:

Very large projects also typically need a feasibility study and go to the Board itself for review, rather than being cleared at officer level. Confirm current timelines with us, since these shift as caseloads and policy change.

Check your project against the exact activity on the BOI's list before relying on a figure. See BOI eligible activities.

Capital need not be in place at the point of application. It must be paid up in full before the promotion certificate is issued, since evidence of the transferred funds forms part of the documentation the Board requires in order to issue it.

The sequence following approval is fixed. The promotion is accepted within thirty days of notification, the capital is transferred from overseas within four months of acceptance, and the company is registered within six months where it is not already incorporated. The certificate follows the submission of a complete set of supporting documents, of which proof of the capital transfer is one.

Capital should be brought in after approval rather than before, and as a single transfer for the exact sum required. Funds arriving early, or in several smaller instalments in place of one exact amount, invite enquiry from the Board and delay issue of the certificate.

For the general rules governing registered and paid-up capital, see registered capital in Thailand. The sequence above corresponds to Step 5 of the process set out in apply for BOI promotion.