A customer asks for daily delivery. Nobody argues, because arguing sounds like arguing against service. Six months later somebody notices the lane is losing money and starts negotiating the rate, which is the one thing on that lane that was never the problem.
Delivery frequency is a price, and it is usually the largest single price nobody has looked at. This is how to work out what yours costs, and what actually happens if you change it.
Daily is not a service level, it is a drop size
Take the same weekly volume and split it different ways. Ten tonnes a week is:
- Five drops of two tonnes, if you deliver daily
- Two drops of five tonnes, if you deliver twice a week
- One drop of ten tonnes, if you deliver weekly
The goods are identical. The kilometres are nearly identical. What changed is the size of one delivery, and drop size is the single thing that decides which vehicle goes out and whether it is full when it does.
So "we deliver daily" and "we deliver in two-tonne lots" are the same sentence. One of them sounds like a promise to the customer and the other sounds like a cost problem. They are the same sentence.
First test: does frequency cost you anything at all?
Before any arithmetic, one question settles whether this article applies to you.
Divide your volume per delivery by the payload of the vehicle you would send.
- If a single delivery already fills that vehicle, your freight is priced by the tonne, not by the trip. Sending 25 tonnes as one trailer today and another 25 tomorrow costs the same as sending 50 tonnes on Friday in two trailers. Frequency here is nearly free, and you should keep it high. Cutting it buys you nothing and costs the customer stock.
- If a single delivery does not fill that vehicle, you are paying for a vehicle and a driver for the day regardless of how little is on the back. Every extra delivery day is a whole vehicle-day. Frequency here is one of the most expensive things on your cost sheet.
Almost every argument about delivery frequency is really an argument between people on opposite sides of that line. Somebody moving full trailers genuinely does not understand what the fuss is about, and they are right about their own lane.
What it costs, on one lane
Take a manufacturer near Bangkok supplying a customer's warehouse in a north-eastern province, ten tonnes a week, steady. These rates are round numbers for illustration; put your own quoted rates for your own lane in their place.
| Vehicle | Payload | One-way rate for this lane |
|---|---|---|
| 4-wheel | 2 t | 5,500 |
| 6-wheel | 6 t | 8,000 |
| 10-wheel | 15 t | 12,000 |
Now run the same ten tonnes at four frequencies, always using the smallest vehicle that carries the drop:
| Frequency | Drop | Vehicle | Per week | Per year |
|---|---|---|---|---|
| Daily, 5 a week | 2 t | 4-wheel | 27,500 | 1,430,000 |
| 3 a week | 3.3 t | 6-wheel | 24,000 | 1,248,000 |
| 2 a week | 5 t | 6-wheel | 16,000 | 832,000 |
| Weekly | 10 t | 10-wheel | 12,000 | 624,000 |
All in baht, 52 weeks.
Going from daily to twice a week takes 598,000 baht a year off one lane. Not off the whole operation. Off one customer.
Notice something in the middle of that table. Moving from daily to three times a week saves almost nothing, because the drop grows past two tonnes and you have to step up to a six-wheeler, which eats the saving. The money is not in trimming a day. It is in getting the drop over the payload of a vehicle you were already paying for.
The other side: what the extra stock costs
Someone now has to hold the goods that are not being delivered. Usually the customer, sometimes you.
Nationally this is not a small offset. NESDC puts Thailand's 2024 logistics costs at 2,509.4 billion baht, of which transportation is 1,200.6 billion, or 47.9%, and inventory holding is 1,122.1 billion, or 44.7%. Two piles almost the same size. A decision that moves cost from one to the other deserves the arithmetic rather than an instinct.
The arithmetic is short. If deliveries arrive at an even rate and get used at an even rate, the average stock created by the delivery pattern is half a delivery. That is all it is.
| Frequency | Drop | Average cycle stock | Extra, against daily |
|---|---|---|---|
| Daily | 2 t | 1.0 t | β |
| 3 a week | 3.3 t | 1.7 t | 0.7 t |
| 2 a week | 5 t | 2.5 t | 1.5 t |
| Weekly | 10 t | 5.0 t | 4.0 t |
Cutting from daily to twice a week creates 1.5 tonnes of extra stock somewhere. That is the whole cost side. Now price it.
Holding stock costs four things: the money tied up in it, the space and handling it needs, insuring and managing it, and the risk that it is damaged, stolen or out of date before it is used. Added up, a quarter of the value of the stock per year is the conventional working figure, and it is the rate the Thai hospital study below used too. The money component alone is not trivial here: NESDC records the minimum loan rate averaging 7.1% in 2024, up from 6.8% in 2023.
So at 25% a year, 1.5 tonnes of extra stock costs 1.5 multiplied by the value of a tonne multiplied by 0.25.
The break-even, in baht per tonne
Set the two sides equal. The transport saving was 598,000 baht a year. The extra stock is 1.5 tonnes.
598,000 = 1.5 Γ value per tonne Γ 0.25
Value per tonne = 1,594,667 baht.
Read that again, because it is the answer to the whole question on this lane. Daily delivery only becomes the cheaper option once the goods are worth about 1.6 million baht a tonne, which is 1,600 baht a kilogramme.
There is a second stock effect, and it does not change this. Delivering less often also lengthens the gap between chances to react to demand, which raises safety stock roughly with the square root of that gap. Going from a one-day interval to a three-and-a-half day interval, on a one-day lead time, raises safety stock by about half. If this lane held one tonne of safety stock under daily delivery, it holds one and a half under twice weekly, so the total extra stock is 2.0 tonnes rather than 1.5. Redo the sum and the break-even falls to about 1.2 million baht a tonne. Still nowhere near ordinary freight.
Nothing in a normal Thai truck is worth 1,200 baht a kilogramme. Packaging, drinks, building materials, food, chemicals, textiles, automotive parts, appliances: none of them are close. Goods that are worth it exist, and they are a short list: medicines, semiconductors, precision instruments, jewellery.
For almost everything that moves on a Thai road, the frequency argument is not close, and it is not close by a factor of ten. That is an uncomfortable finding if daily delivery is something you have been selling, and it is worth knowing before the next rate negotiation, because the rate is not where the money is.
Why a Thai hospital reached the opposite answer
The opposite result exists, is measured, and is worth understanding, because it shows exactly which assumption flips.
A 602-bed general hospital in Thailand had its medicine inventory studied against three alternatives. Current practice was to order three months of use at a time, holding 15 days of safety stock against a five-day lead time. That turned inventory 6.31 times a year on an average inventory value of USD 1,646 thousand.
The second scenario simply ordered one month at a time instead of three. Turnover rose to 12.80, average inventory fell 44% to USD 915 thousand, and total inventory management cost fell 47%.
Tripling the order frequency was straightforwardly the right answer there. Two things made it so, and neither is present on a truck lane:
The goods are worth an enormous amount per kilogramme. Medicines sit far above the break-even calculated above, so the stock side of the trade-off dominates instead of the transport side.
A delivery costs almost nothing. The hospital was placing over 3,000 orders a year at USD 4.64 to 11.60 each, which at any recent exchange rate is somewhere between one and five hundred baht. Compare that with a truck delivery on the lane above at 5,500 to 12,000 baht. Ordering more often costs a few hundred baht a time. Delivering more often costs a vehicle-day.
That is the general rule, and it explains both cases at once: frequency should be high when a delivery is cheap and the goods are valuable, and low when a delivery costs a vehicle-day and the goods are ordinary. Everything else is detail.
There is one more detail in that study worth keeping. Tripling the order frequency cut inventory by 44%, not by the two-thirds the cycle stock arithmetic on its own suggests. The safety stock did not shrink, because safety stock is there for demand you cannot predict, and ordering more often does not make demand more predictable. The same asymmetry protects you going the other way: cutting frequency raises cycle stock in proportion, but it barely touches safety stock.
What actually forces daily delivery
Four things genuinely do, and inventory cost is not one of them.
Shelf life. Fresh food, chilled and unpasteurised products, anything with a short date. If the goods will not survive three days at the customer, frequency is not a cost decision at all.
No space at the receiving end. This is the most common real reason, and it is usually undeclared. A customer with no racking and a small yard cannot take five tonnes. Their daily delivery is not a service preference, it is a warehouse, and you are the one paying rent on it. Before you accept a daily schedule, ask to see where the goods would go if two days' worth arrived at once. The answer often solves the problem: a small amount of racking at their site is cheaper than 598,000 baht a year of your trucks.
Demand you genuinely cannot forecast a week out. Real in some trades, claimed in many more. The test is whether last year's data supports it. If weekly volume varies by 10% and daily volume varies by 60%, the customer does not have unpredictable demand; they have an unpredictable ordering habit, and that is fixable.
Cash and consignment. A customer who pays on delivery, or who cannot carry the stock on their balance sheet, has a financing reason for small frequent drops. That is a legitimate constraint, but it is a finance conversation, not a logistics one, and it should be priced as one.
Notice that none of those four is "because service is better". Service is the next section, and it does not go the way most people assume.
Does twice a week actually serve better?
Sometimes. Not automatically. Frequency, reliability, lead time and stock availability are four separate things that get discussed as one, and customers rate them separately when they are actually asked.
What a fixed twice-weekly schedule genuinely gives you:
A booking a carrier will protect. A daily drop of two tonnes is filler. It goes on whatever vehicle has room, as one of a dozen drops, and it is the first thing bumped when the round runs late. Two full six-wheelers on fixed days are a planned job with a known vehicle and a known driver. Reliability comes from being worth planning around.
Fewer hours spent receiving. At the beverage distribution operator measured above, a vehicle arriving at its main centre took an average of 38 minutes from arrival to the goods being put away, with seven staff on the job. That is roughly 4.4 staff-hours per arrival. Five arrivals a week is about 22 staff-hours; two is about 9. Cutting the schedule hands the receiving site back around 13 staff-hours a week, every week, and takes three vehicles a week out of its yard. If the customer's dock is congested, this is worth more to them than the delivery they gave up.
A better vehicle. Five tonnes on a six-wheeler going to one place behaves differently from two tonnes as drop nine of fifteen. Arrival windows get tighter, handling gets simpler, and damage falls, because the load is not being shuffled at four other sites first.
What it genuinely takes away:
The maximum wait doubles or worse. Under daily delivery, something that runs out on Wednesday morning arrives Thursday. Under a Tuesday and Friday schedule it arrives Friday. That is the real service cost, and it should be stated plainly rather than glossed over.
Mistakes wait longer. A short shipment, a damaged pallet or a picking error is normally fixed on the next delivery. On a twice-weekly schedule that is three days away instead of one. The honest fix is not to pretend otherwise, but to agree an exception run and price it as an exception, so a genuine emergency has a route that does not require rebuilding the whole schedule.
Two Thai constraints worth checking first
The driving day. Under Section 103 bis of the Land Transport Act B.E. 2522, in a twenty-four hour cycle a licensed driver may not drive more than four consecutive hours from starting, and after a break of at least half an hour may drive up to four more. Eight hours of driving in a day is the Act's own ceiling, and the section is expressly subject to the labour protection law on top of that.
That ceiling is why frequency is expensive on long lanes and cheap on short ones. On a lane where the round trip fits comfortably inside one driver's day, an extra delivery day costs one vehicle-day. On a lane where it does not, an extra delivery day costs two, because a driver has to sleep somewhere. Work out how many driver-days one delivery consumes before you decide how many deliveries a week you can afford. The same subtraction decides how much notice a booking needs.
Arrival windows and holidays. In Bangkok the expressway network is closed to six-wheelers between 06:00 and 09:00 and between 16:00 and 20:00, and to ten-wheelers and trailers between 06:00 and 09:00 and between 15:00 and 21:00. A daily schedule has to survive that five times a week, and it is why daily deliveries drift later and later in the day. A twice-weekly schedule can be built around the open hours instead of fighting them. The same is true of long holidays: a fixed low-frequency schedule absorbs Songkran by moving one delivery, while a daily one has to be rebuilt.
Changing it without a fight
The mistake is to announce a frequency cut. Frequency is not a rule you set, it is an outcome of a minimum drop size, and that is what to change.
- Set a minimum drop, not a maximum number of days. "Any order over four tonnes goes on the next scheduled run" leaves the customer in control and produces the outcome anyway.
- Price the choice instead of removing it. Give the customer both, with the difference visible. Most will take the cheaper one once it is a number on a page rather than a service being withdrawn. The ones who do not have a reason, and now you know what it is.
- Do it customer by customer, not as a policy. The right frequency is a property of the lane, and it differs. A customer taking forty tonnes a week can have daily delivery on full vehicles for nothing. A customer taking two tonnes a week cannot have it at any sensible price.
- Fix the ordering pattern before the delivery pattern. Half the daily deliveries in Thailand exist because somebody orders whenever they notice a gap on a shelf. A weekly order day removes more trips than any schedule change, and nobody experiences it as a service reduction.
- Check who is holding the stock afterwards. If you cut frequency and simply push the stock onto the customer, you have moved cost rather than removed it, and they will eventually price it back to you. If the stock lands where it is cheapest to hold, both sides keep something.
What to change on Monday
- Take your three largest customers, divide weekly volume by the payload of the vehicle you send them, and find out which side of the vehicle-day line each one sits on. Frequency only costs money on one side
- For any lane where a drop does not fill a truck, multiply the delivery rate by the number of deliveries a year. That number is what frequency costs you on that lane, and it is usually larger than anything under negotiation
- Work out the value of a tonne of what you ship. If it is under a million baht a tonne, stop treating the stock cost as an argument against delivering less often, because it is not one
- Before accepting or defending a daily schedule, go and look at the customer's receiving area. If the reason is space, the cheap fix is at their site, not on your trucks
- Count the staff-hours your own dock spends receiving. Three fewer arrivals a week is real labour, and it is a benefit the receiving site feels immediately
- Check whether one delivery on your longest lane consumes one driver-day or two. If it is two, every delivery day costs double what the rate sheet suggests
- If you change anything, change the minimum drop size and let the frequency follow. Announcing fewer deliveries starts an argument; announcing a drop size starts a conversation about order patterns
The trade-off is real and it is worth doing properly, but it is not balanced. On one side is a vehicle and a driver for a day. On the other is a quarter of the value of half a delivery. For ordinary goods those are not the same size, and the honest cost per unit only shows up when you pick a denominator that does not hide the vehicle-day. It is the same reason that drop size, not distance, decides whether a hub pays: almost everything expensive in road freight is priced by the day, and the day is what a small delivery wastes.