1. Keep every offer, with its date
You only see an increase by comparing. A price list overwritten by the next one is an increase you will never see. So keep every offer as it came, dated, filed by supplier: the Excel file, the CSV, but also the WhatsApp message or the e-mail announcing “new prices this week”.
The date matters as much as the price. It says which offer is the previous one, and how long a price has held.
2. Compare today's offer with the previous one
Reference by reference, match the new offer against the same supplier's previous one, and put every line in one of these boxes:
- Increase: the price went up since the previous offer.
- Decrease: it went down. Worth noting too: a decrease at one supplier is an argument with another.
- Dropped: the reference disappeared from the list. End of line, shortage, or a price the supplier no longer wants to hold: information either way.
- New: the reference appears for the first time.
Add one last column: for every reference, the best price at your other suppliers. A 5 % increase does not weigh the same when someone else already sells 15 % cheaper.
3. Separate the supplier's increase from the exchange rate
A dollar price that does not move can cost you more in euros if the euro has fallen. That is not a supplier increase, and it is not with the supplier that it gets negotiated. Conversely, an increase in dollars can go unnoticed if the exchange rate offset it.
The rule: convert both offers at the same rate. The gap that remains is the supplier's, the only one to discuss with them. The exchange rate is managed separately.
4. Put a figure on what is at stake
A list of increases weighs nothing until it has a figure. Add up, per unit:
- the increases since the previous offer;
- the gaps to the suppliers selling the same reference for less.
Three increases at one supplier: +€3.60, +€1.50 and +€1.50 per unit, €6.60 in all. On three references, other suppliers sell for less: €18.45 of gaps per unit. Amount at stake: €25.05 per unit, across 5 references.
Multiply by your quantities: that is the figure to negotiate.
5. Negotiate with facts
The supplier knows their prices better than you. To talk as equals, come with:
- The increases, line by line, with the price before, the price after and the date of both offers.
- The cheaper offers, without necessarily naming the competitor: “this reference is offered 15 % cheaper” is often enough.
- The dropped references: are they replaced, and at what price?
- A precise request: back to the previous price on this reference, or held until this date for this quantity.
Ask for the reason behind each increase too: raw materials, freight, exchange rate. A justified increase is discussed on its duration; an unjustified one is simply discussed. Then keep the answer: the next offer will tell whether the commitment held.
A monthly rhythm
Take stock once a month, supplier by supplier: increases, decreases, dropped references, and the five biggest increases in euros per unit. A month is long enough for gaps to show, not long enough for them to settle in.