If you are a TikTok Shop Thailand seller in the 6.42% to 11.77% commission band who is being asked to fund a 15% voucher for the 7 to 12 November window, and cannot tell whether the voucher costs what the discount says it costs, the decision in front of you is not how deep the voucher goes. It is what share of it you fund, and how many more units that share has to sell before it pays for itself. Two sellers list the same THB 1,200 product, fund the same 15% voucher, sell the same number of units, and end the campaign with different margins. The difference is not the discount and not the traffic. It is that one sits at 5.35% and the other at 11.77%, and on a THB 1,200 basket that six-point gap moves the break-even volume by fourteen percent before you have sold a single unit.
Take a THB 1,200 basket at 55% cost of goods, so THB 660. Before any voucher, at 6.42% commission and 3.21% transaction fee, you keep THB 424.50; at 11.77% you keep THB 360.30; at the Mall floor of 5.35% you keep THB 437.30. Now fund a 15% voucher. The buyer pays THB 1,020, and because both fee lines are charged on what the buyer pays, they fall as well: commission drops to THB 65.50 at 6.42%, THB 120.10 at 11.77% and THB 54.60 at 5.35%, while the transaction fee drops to THB 32.70. Net profit becomes THB 261.80, THB 207.20 and THB 272.70. So the voucher costs you THB 162.70, THB 153.10 and THB 164.60 depending on the band, against a headline discount of THB 180, and the volume you need to break even is 1.62 times, 1.74 times and 1.60 times. Same voucher. Three different prices.
Two commission bands, one voucher, two different bills
Thai commission is not one number. Sellers outside the Mall programme are quoted in a band that runs from 6.42% up to 11.77% depending on category, and sellers inside Mall are quoted from 5.35% up to the same 11.77% ceiling. That is a 6.42-point spread inside a single market, and it acts on every baht of discount you fund. Layer on top of it the 3.21% transaction fee, whose base changed on 21 March 2026 so that discounts funded by the platform are now included rather than excluded. Those two things together mean a voucher is never priced at its face value, and the error is always in the same direction: sellers under-estimate what their own voucher costs, because they compare it to the discount rather than to the net profit change.
The 3.21% line is the one most sellers have never looked at, and it is the one that most cleanly answers whether a platform-funded discount is free. It is not. If the platform funds a 10% discount on a THB 1,200 basket, that is THB 120 of discount you did not pay, and the transaction fee on it is THB 3.85 that you did pay. On one order that is a rounding error. Across 8,000 orders in a month it is THB 30,800, and it grows with every extra point of platform discount, which means the deepest platform campaigns are also the ones where this line is largest.
Step 1 — Convert the voucher into what leaves your account, not what the tag says
The mistake is to read the voucher off the tag. A 15% voucher on a THB 1,200 basket is not THB 180 out of your pocket, because the commission and the transaction fee are both charged on what the buyer actually pays, and that number has just fallen. Work forwards, not backwards: compute net profit with no voucher, compute net profit with the voucher, and take the difference. At 6.42% the difference is THB 162.70, which is 13.6% of the tag rather than 15%. At 11.77% the difference is THB 153.10, or 12.8% of the tag. At 5.35% it is THB 164.60, or 13.7%. The voucher always costs less than its face value, and the size of the gap is set entirely by your commission band.
That 13.6% versus 12.8% gap looks small until you multiply it out. On 1,000 orders in the six-day window it is THB 9,600 of difference in what the same voucher costs two sellers with the same product, the same discount and the same volume. It is also why a seller who moved into Mall and saw the commission fall from 11.77% to 5.35% did not simply gain six points of margin: their voucher got slightly more expensive at the same time, because the fees that cushion it fell too. The two effects partly cancel, and the net is smaller than the commission change suggests.
If you would rather not build the two-band comparison by hand, the campaign cost sheet is on the dashboard page — register with DAMI and ask the team for the campaign cost sheet and it prices the same voucher at both ends of the commission band for your basket size.
Step 2 — Run the arithmetic at both ends of the band you are in
Run the arithmetic twice, once at the floor of your band and once at the ceiling, and keep both answers. At 5.35% the THB 1,200 basket gives you THB 437.30 before the voucher and THB 272.70 after, a break-even of 1.60 times volume. At 11.77% it is THB 360.30 and THB 207.20, a break-even of 1.74 times. The point of running both is not precision: it is to find out whether the answer changes enough to matter. A gap of 1.60 against 1.74 means that for one seller the campaign works at a modest lift, and for the other it needs a lift that the six-day window rarely delivers. If your band is narrow, the run is quick. If it is wide, you have found the real risk in the plan.
Write down which band you are actually in before the meeting, because the number is public to you and rarely stated out loud. Most sellers quote the number they remember from onboarding, which is the figure for their first category and not necessarily the one they sell in now. If you have added a category in the past year, or moved between Mall and non-Mall, the rate you are being charged is not the rate in your head. That single correction is usually worth more than any optimisation of the voucher depth, because it changes the break-even multiple on every SKU at once.
Step 3 — Add the platform-funded discount back into the 3.21% base
The transaction fee base change is the quiet one. Since 21 March 2026, discounts funded by the platform are included in the base on which the 3.21% is charged. Before that date a platform-funded discount was excluded, so it genuinely cost you nothing on this line. Now it costs you 3.21% of the discount. The practical consequence is that you should stop treating platform discounts as free margin help and stop treating seller-funded vouchers as the expensive option: a seller-funded voucher of 15% costs you 15% and reduces your other fee lines, while a platform-funded 15% costs you 3.21% of 15% with no reduction anywhere. On a small basket the platform discount is still cheaper. It is just no longer free, and the difference has to be written into the comparison.
There is one more asymmetry worth pricing. A seller-funded voucher reduces the buyer's payment, and therefore reduces both the commission and the transaction fee base. A platform-funded discount does not reduce your commission base at all in the same way, but it does add to the transaction fee base. So on this market the two discount types are not interchangeable even at the same depth: a 15% voucher you fund and a 15% platform discount are different transactions on your P&L, and only one of them comes with a fee reduction attached. When someone proposes a campaign, ask who funds the discount before you ask how deep it is.
Step 4 — Six days in November, so count days rather than the campaign
The window is 7 to 12 November, six days, not the full campaign period sellers tend to quote in planning. Six days is roughly one fifth of a month, so a break-even multiple of 1.74 has to be read against a baseline that is already compressed. If a normal week gives you 700 orders, six days of normal trading give you about 600, and 1.74 times that is 1,044 orders. Whether the campaign can generate 1,044 orders in six days is a question about your traffic and your stock, not about your discount. Run that number before you agree to the voucher, because once the campaign starts the only lever left is stock, and running out is worse than not joining.
Six days also means the voucher should not be flat across all six. The first two days are discovery, when traffic is cheap and conversion is low, and the last two are decision, when traffic is expensive and conversion is high. A voucher that is live at full depth for all six days pays discovery traffic a discount it would have converted without. The usual fix is to hold the deepest depth for the final 48 hours and run a shallower one before that, which lowers the average funded depth without lowering the conversion on the days that actually close orders.
Where DAMI fits: three moves that put both bands on one sheet
DAMI brings an 8-million-plus creator database, competitor and competitor-store creator search, automated outreach tasks, AI-assisted outreach, AI video creation, sample management, campaign management, social media management, store analytics, and multi-store team dashboards into one place. Three moves cover this, and each one leaves you with a file you can put in front of whoever approves the discount.
Move 1 — Confirm your commission band from the fee page, not from memory
Read the actual rate applied to your category and note whether you are inside or outside Mall. The output is one number and one word, and it replaces the figure you have been quoting since onboarding.
Move 2 — Price the voucher twice, at the floor and the ceiling of that band
Compute net profit before and after the voucher at both ends, take the difference, and divide the before figure by the after figure. The output is a pair of break-even multiples, 1.60 and 1.74 in the example above, that tell you how much the answer depends on a number you do not control.
Move 3 — Add the platform-funded discount into the 3.21% base
Take the platform discount in the proposed campaign, multiply by 3.21%, and add it to the cost side. The output is a single line that stops the meeting from treating platform money as free money.
Questions sellers ask before they fund the voucher
Is the commission band fixed for the whole year?
It is set by category, not by campaign, so it does not change because you join 11.11. What does change is the amount it is charged on, because the fee follows the price the buyer pays. That is why the same rate produces a smaller fee during a promotion than outside it.
Do I pay commission on the discount I fund?
No, and that is the part sellers miss in the other direction. Commission is charged on what the buyer pays, which is the price after your voucher. So a 15% voucher leaves you paying commission on 85% of the tag, not on 100%. The fee reduction is real and it is why the voucher costs less than its face value.
Then why is the platform-funded discount different?
Because the transaction fee base was changed on 21 March 2026 to include discounts funded by the platform. Your commission base is still what the buyer pays, but the 3.21% line now also carries a share of the platform's own discount. One line shrinks with discounts you fund, the other grows with discounts the platform funds.
Does Mall membership change the answer?
It changes the starting rate, from as low as 5.35% inside Mall against 6.42% outside, but it does not change the break-even formula. What it does change is the gap between the two ends: a seller inside Mall with a narrow band gets a far more predictable answer than a seller outside whose category spans the full range.
I am already committed and the window opens on 7 November. What can still be adjusted?
The depth, if the terms allow a stepped voucher, and the product selection the voucher applies to. Both change the funded amount without touching the fee rate. What cannot be changed at that point is the commission band, which is why confirming it first matters more than any tuning afterwards.
The one number to check on 13 November
Every voucher in this piece is a ratio question wearing a percentage sign. The percentage tells you what the buyer sees; the ratio tells you how much more you have to sell. DAMI brings an 8-million-plus creator database, competitor and competitor-store creator search, automated outreach tasks, AI-assisted outreach, AI video creation, sample management, campaign management, social media management, store analytics, and multi-store team dashboards into one place.
Open the fee page, find the rate applied to the category you actually sell in today, and write it at the top of a blank sheet. Then put THB 1,200 and THB 660 on the next two lines and compute net profit twice, once at that rate and once at the other end of the band. Fifteen minutes, and you will know whether the voucher in the campaign plan costs you 1.60 times the volume or 1.74 times. Everything else in the meeting is a detail.
Start with DAMI and put the ratio next to the discount before the campaign puts it on your P&L for you.
