Can a supplier increase prices during a contract?

Can a supplier increase prices during a contract? The starting point is the agreement itself. A supplier may be able to raise prices where the contract contains a valid price-review mechanism, where the parties agree a variation, or when a committed term ends and a new price takes effect. A supplier does not have a general right to rewrite a fixed price merely by sending a higher invoice.

This article is general information, not legal advice. It focuses on business-to-business contracts governed by the law of England and Wales; consumer pricing rules are different.

Is the price actually fixed?

A contract may appear to state a price but make it variable elsewhere. Read the order form, pricing schedule, master agreement, renewal clause and incorporated online terms together.

Common structures include:

• Fixed price: the stated amount applies for a defined supply or term.
• Rate card: work is charged at listed hourly, daily or unit rates.
• Estimate: the final charge depends on actual time, quantities or costs.
• Indexation: prices change by reference to CPI, RPI or another published index.
• Cost pass-through: specified taxes, duties, energy, freight, materials or third-party charges can be passed on.
• List-price wording: the customer pays the supplier’s “then-current” rates.
• Review and agreement: the parties must negotiate or agree a revised price at stated intervals.
• Renewal pricing: a fixed initial price changes when the contract automatically renews.

The label is not decisive. A “fixed” annual subscription may still contain a separate right to increase fees at each anniversary.

When can a supplier increase the price?

There are four common routes.

1. The contract contains a price-increase clause

A clause may permit an increase on a particular date or after a minimum period. The supplier must follow the mechanism: notice, timing, calculation and any cap or customer exit right.

For example:

On each anniversary, the Charges may increase by the percentage increase in CPI over the preceding 12 months, subject to a maximum increase of 5%.

That is more predictable than wording allowing the supplier to increase prices “from time to time” at its discretion.

2. The parties agree a variation

The parties can agree to change a price, but the contract may specify how variations must be made. It may require a signed written document, approval by named representatives, or a formal change-control process.

The UK Supreme Court has confirmed that clauses requiring contractual variations to be made in a specified written form can be legally effective. An informal call or email from an unauthorised employee may therefore be insufficient.

Case reference: Rock Advertising Ltd v MWB Business Exchange Centres Ltd [2018] UKSC 24.

3. The customer changes the scope

A higher charge may result from additional work rather than a change to the original price. The contract should explain how changes to quantities, specifications, delivery dates, assumptions or service levels affect fees.

A supplier should not rely on “scope creep” as an informal pricing mechanism. A customer should not assume extra work is included merely because the original contract has a fixed price. A written change request should state both the revised work and its price effect.

4. The existing commitment ends

A supplier may offer a new price for a new order or renewal term. The customer’s rights depend on the renewal wording and any notice deadline. If the contract automatically renews at the supplier’s current rates, missing the non-renewal window may result in another term at a higher price.

Related reading: Automatic renewal clauses: avoiding auto-renewal lock-ins.

What if the contract does not set a price?

English law can imply a reasonable price or charge in some business contracts where the consideration has not been determined by the agreement.

For sales of goods, section 8 of the Sale of Goods Act 1979 provides that the price may be fixed by the contract, fixed in an agreed manner, or determined by the parties’ course of dealing; where it is not determined, the buyer must pay a reasonable price. For certain services, section 15 of the Supply of Goods and Services Act 1982 similarly implies a reasonable charge where the consideration is not determined.

That is not the same as a supplier having an unrestricted power to choose any figure after the work is done. What is reasonable depends on the circumstances, and disputes over an unstated price are expensive and uncertain.

Official legislation: Sale of Goods Act 1979, section 8 and Supply of Goods and Services Act 1982, section 15.

Warning signs in price-increase clauses

Look closely for:

• Unlimited discretion. The supplier can increase prices by any amount for any reason.
• No minimum notice. A new price can take effect immediately or retrospectively.
• No exit right. The customer remains locked in after a material increase.
• Vague cost language. “Increased costs” are undefined and need not be evidenced.
• Multiple increase mechanisms. Indexation, list-price changes and cost pass-throughs can all apply to the same charge.
• Compounding. An annual percentage is applied to the already increased price.
• A floor but no cap. The price rises by at least a stated amount even if the index falls.
• Cherry-picked indices. The supplier can choose whichever index produces the highest result.
• Changes to existing orders. A general price right may purport to affect work already ordered or paid for.
• Online terms controlled by one party. The supplier can replace the version incorporated into the signed deal without a clear notice or acceptance process.

A right to increase prices is not automatically unreasonable. Suppliers may face real inflation, wage, energy, tax or third-party cost changes. The question is whether the mechanism identifies the risk being transferred and gives both sides a workable way to plan.

What should a balanced clause address?

A more predictable price-review clause may specify:

1. Timing: for example, once per contract year.
2. Notice: a stated number of days before the increase takes effect.
3. Method: a formula, index or defined cost category.
4. Evidence: supporting information for pass-through costs.
5. Cap and floor: limits on upward and downward adjustment.
6. Scope: which fees, products or future orders are affected.
7. No double counting: one cost increase should not be recovered through several mechanisms.
8. Customer response: acceptance, negotiation or a right to terminate before the new price applies.
9. Renewal interaction: whether the new price applies during the current term or only on renewal.
10. Change control: who is authorised to agree a different price and in what form.

A practical response to an unexpected increase

When a supplier announces a price rise, do not start with the invoice alone. Find the complete contract and ask:

• Which clause permits the increase?
• Has the supplier used the required calculation?
• Was notice served correctly and on time?
• Does the increase apply to existing commitments or only future orders?
• Is there a cap, negotiation period or termination right?
• Has the customer’s conduct already accepted the change?

Continuing to order, use the service or pay the increased amount may affect the parties’ position, depending on the wording and circumstances. If the amount is material, record any objection promptly and obtain advice before withholding payment or terminating.

The safest pricing mechanism is not necessarily a permanently fixed price. It is one that makes the timing, calculation and consequences of change clear before either side commits.