How to order 80 days ahead without guessing

Short answer: when goods take 80 days to arrive, start with a rolling sales forecast: base sales, minus expected dips, plus promo lift. Then order enough to cover the lead time, the days until the next order and your safety stock. Take off stock on hand and stock on the way. A person approves the order.

The problem: you order before you know

Take a lubricants distributor we work with. From order to warehouse takes 75 to 80 days. Pricing. Prepayment. A month of making. A month of shipping.

So goods for January must be ordered in early October.

But in early October, there's no sales plan for three months ahead. So they order blind. And cash gets frozen in stock.

The plan lived in a big Excel rolling forecast. Sales, supply and marketing filled it in by hand.

And lead times don't hold still. Shipping routes can close and change them.

Step 1: build the sales plan

Start with one simple formula:

plan = base sales − dips + promo lift

• Base sales: what you usually sell. Use your sales history, but take out past promotions. Otherwise last year's big sale looks like normal demand.
• Dips: months you expect to sell less, like a holiday month.
• Promo lift: extra sales you expect from a planned promotion.

Here's an example. These are made-up numbers, not the client's.

Month	Base sales	Dips	Promo lift	Plan
January	300	−30	0	270
February	300	0	+60	360
March	300	0	0	300

Do this for six months ahead, and roll it forward every month. That's a rolling forecast. We call it a forecast on purpose. Nobody knows the future. A good forecast shows its reasons, so people can disagree with it.

Step 2: work out how much to order

Now turn the plan into an order. You need enough to last until the next order can arrive, plus a cushion.

order = daily plan × (lead time + days of cover + safety days) − stock on hand − stock on the way

Another example. Again, made-up numbers.

Input	Value
Daily plan	4 units
Lead time	80 days
Days of cover after it arrives	30 days
Safety stock	15 days
Needed: 4 × (80 + 30 + 15)	500 units
Stock on hand	220 units
Stock on the way	172 units
Order now	108 units

Then check the minimum order. If the supplier's minimum is higher, you either order the minimum or wait.

Step 3: show only the choices that matter

This is the part most tools get wrong.

In the pilot, we built all of it:

• a 6-month rolling forecast from sales history, cleaned of past promotions;
• order amounts with the 80-day lead time, the minimum order and 15 days of safety stock;
• purchase orders you approve, email to the supplier in one click, and mark as received.

A person approves every order.

We also built a daily "Today" screen with the few choices that matter. Lines like:

• "Move 120 units from one warehouse to another."
• "Order 108 units, arriving 22 Feb. Covers 30 days plus 15 days of safety stock."

What the team told us

On 3 Nov, the team gave us honest feedback. The logic is strong. But the screen is too complex.

Their words, roughly: not a chat. A simple screen, like a weather forecast. You see it, you understand it, you act.

They're right. A forecast nobody reads is worth nothing.

So we split it into blocks. We start with sales, and the screen is being made simpler now.

A checklist for long lead times

1. Clean your history. Take past promotions out before you forecast.
2. Write the plan as a formula. Base, minus dips, plus promo lift.
3. Roll it forward monthly. Six months ahead.
4. Know your real lead time. And watch for routes that change it.
5. Set safety stock in days. It's easier to talk about than units.
6. Count stock on the way. It's the line people forget.
7. Show only today's choices. Hide the maths behind them.
8. Keep a person on every order. The maths drafts. People decide.

The short version

You can't know the future. But you can stop guessing. A plain formula, a rolling forecast and a short daily list turn an 80-day bet into a choice you can explain.

Read the full story: How a lubricants distributor plans orders 80 days ahead

If your goods take weeks or months to arrive and your plan lives in a spreadsheet, we can look at it with you. Book a free audit