CPI Rent Reviews in Commercial Leases: Landlords vs Tenants

If you’re leasing a shopfront, office, warehouse, or industrial space, rent is probably one of your biggest ongoing costs. So when the lease says “rent will increase each year by CPI”, it’s normal to wonder what that really means in practice (and whether it’s fair).

A CPI rent review is one of the most common rent review methods in Australian commercial leases. It’s often seen as a “middle ground” option: not as unpredictable as market rent, and not as aggressive as large fixed percentage increases. But the detail matters.

In this guide, we’ll break down what CPI rent reviews are, how they’re calculated, what to look out for in your lease, and how landlords and tenants can negotiate CPI clauses so there are fewer surprises later.

What Is A CPI Rent Review (And Why Is It So Common)?

A CPI rent review is a rent increase (or adjustment) based on the Consumer Price Index (CPI), which is a measure published by the Australian Bureau of Statistics (ABS) that tracks changes in the cost of goods and services over time (in other words, inflation).

In many commercial leases, CPI is used as a way to keep the rent broadly aligned with inflation. The idea is:

• the landlord’s costs may rise over time (insurance, maintenance, financing costs, rates, etc.); and
• the tenant avoids steep rent jumps that can happen with fixed increases or market reviews.

CPI rent reviews usually occur at set times, commonly:

• annually (e.g. each anniversary of the lease commencement date);
• at option periods (when a tenant exercises an option to renew); or
• at other review dates specified in the lease.

CPI clauses are most often used in longer-term commercial leases where both sides want some predictability.

CPI Rent Review Vs Fixed Increase Vs Market Review

To understand whether a CPI rent review is “good” for you, it helps to compare the main options:

• CPI rent review: Rent changes by inflation. Usually steadier and more “economic conditions”-linked, but can still rise sharply during high-inflation periods.
• Fixed increase: Rent increases by a set amount or percentage (e.g. 3%, 4%, or 5%) regardless of inflation. Predictable, but may be above CPI for long periods.
• Market review: Rent changes to match market rent for comparable premises. Can go up a lot (and sometimes down, depending on drafting and any applicable retail leasing rules).

A well-drafted lease can also mix methods (for example, CPI annually, and market review at the start of an option period).

How Does A CPI Rent Review Work In Practice?

Most CPI rent review clauses work by comparing CPI figures at two points in time (for example, the CPI at the start of the lease and the CPI at the review date), and then applying that percentage change to the current rent.

Here is the most common structure you’ll see:

• Base rent (your current rent immediately before the review date)
• multiplied by the CPI movement (the % change between the base CPI figure and the current CPI figure)
• equals new rent

A Simple Example Calculation

Let’s say:

• Current rent: $60,000 per year
• Base CPI (at last review): 130.0
• Current CPI (at this review): 134.0

The CPI movement is:

(134.0 - 130.0) / 130.0 = 0.0307 (about 3.07%)

New rent would be approximately:

$60,000 x (1 + 0.0307) = $61,842

That’s the broad concept. But the exact calculation depends on how the clause is written (and some clauses are more landlord-friendly than others).

Which CPI Figure Is Used?

This is where disputes can start if the lease isn’t clear. A CPI clause should specify things like:

• which CPI series (e.g. All Groups CPI);
• which city/capital index applies (or whether it’s a weighted national figure);
• whether it uses a quarterly index number, and which quarter;
• what happens if the CPI series is replaced or restructured by the ABS; and
• what happens if the CPI number is not yet published by the review date.

If you’re negotiating a lease, clarity here is one of the best ways to reduce friction later.

Key CPI Rent Review Clauses To Check Before You Sign

A CPI rent review clause can look simple on the surface, but a few “extra” features can make a big difference to the outcome. Whether you’re a landlord or tenant, these are the items worth checking closely (ideally before you commit to the lease).

Is There A Minimum Increase (A CPI “Floor”)?

Some clauses say the rent will increase by CPI or a minimum percentage (for example, “CPI or 3%, whichever is greater”). This is sometimes called a CPI floor.

For tenants, a floor can be a problem because:

• in low-inflation periods, you still pay a high fixed increase; and
• the clause may effectively become a fixed-increase lease, not a CPI lease.

For landlords, a floor can create predictable rental growth even if inflation is low.

It’s not “wrong” to have a floor, but it should be negotiated openly because it changes the commercial risk allocation.

Is There A Maximum Increase (A CPI “Cap”)?

Some leases include a cap (for example, “CPI up to a maximum of 5%”).

This can help tenants manage risk in high-inflation periods. From a landlord perspective, a cap can be acceptable if it’s balanced with:

• a market review at option time; or
• a higher starting rent or longer lease term.

If you’re a tenant signing a long-term lease, asking for a cap is a common negotiation point, especially if your business has tight margins.

Does The Clause Allow Rent To Go Down If CPI Is Negative?

Occasionally, CPI can be flat or even negative. Many CPI rent review clauses are drafted so rent only ever increases (for example, “rent will be adjusted by CPI, but not reduced”). This is sometimes referred to as a “ratchet” clause.

For tenants, it’s worth checking:

• if CPI is negative, does rent stay the same, or can it reduce?
• if rent is “not reduced”, does the clause still treat the prior CPI as the base figure next year?

For landlords, ratchet drafting is common, but it should still be clear and consistent with the rest of the rent review mechanism.

What Happens If There’s Also A Market Review?

Some leases combine CPI reviews with market reviews. For example:

• annual CPI reviews; and
• a market review at the start of an option term.

This structure can be workable. The key is to ensure the lease clearly states:

• which review applies on each review date; and
• how conflicts are dealt with if review dates overlap.

If the drafting is messy, it can create disagreement right when you’re trying to renew your lease (which is usually a high-pressure time for tenants).

What Landlords Need To Know About CPI Rent Reviews

If you’re a landlord, CPI rent reviews are often attractive because they provide a rent escalation mechanism that’s tied to real-world conditions, and they are usually easier to administer than a full market rent valuation process.

That said, CPI drafting can still create risk if it’s too vague or too aggressive.

Make The CPI Clause Clear And Administrable

A good CPI clause should reduce back-and-forth. That means specifying:

• the exact CPI series (and the reference quarter);
• the mathematical formula (so there’s no ambiguity); and
• a process and timing for issuing a rent review notice to the tenant.

Even if you have a great relationship with the tenant now, clarity helps protect you if the relationship changes or the premises are sold and the lease is assigned.

Be Careful With “CPI Or X%” In Retail Leasing

If your premises is covered by retail leasing legislation, there can be rules about which rent review mechanisms are allowed and what must be disclosed - depending on the state or territory.

For example, retail leasing rules differ across Australia, and may affect things like how market rent reviews work, what disclosure statements are required, and (in some jurisdictions) whether “ratchet”-style drafting is permitted. Because the rules are location-specific, it’s worth getting advice on your particular lease and premises before you rely on a clause long-term.

Consider The Rest Of The Lease Risk Settings

A CPI rent review clause doesn’t exist in isolation. Landlords often also rely on:

• outgoings recovery provisions (so you can recover agreed operating costs);
• security arrangements (bank guarantee, bond, or personal guarantees); and
• clear default and termination clauses.

Because the lease is doing so much “risk management” work, it’s worth treating it like a key business asset and not just a template document. If you’re negotiating an important lease, having it Commercial Lease Reviewed can help make sure all the moving parts align, including the rent review mechanism.

What Tenants Need To Know Before Agreeing To A CPI Rent Review

If you’re the tenant, a CPI rent review can be a reasonable option, but it’s still something you should actively assess rather than accept by default.

When you sign a lease, you’re locking in your occupancy cost structure. If rent grows faster than your revenue, the lease can become a pressure point for your business.

Check Whether CPI Is Being Used As “Code” For Regular Large Increases

On paper, CPI sounds modest. In reality, CPI can move significantly, and if the lease includes:

• a CPI floor (e.g. minimum 4%);
• a ratchet (never decreases); and
• outgoings that are also increasing each year,

your total occupancy costs may rise faster than you expect.

This is especially important if you’re setting prices annually, operating in a competitive area, or dealing with fixed-fee customer contracts.

Ask For A Worked Example Before You Commit

One practical negotiation approach is to ask the landlord (or agent) for a worked example showing what the CPI clause would have done over the last 3–5 years.

This isn’t a legal requirement, but it helps you stress-test affordability and cashflow.

Think About Options, Fit-Out Costs, And Your Exit Plan

CPI reviews matter even more when:

• you’re spending money on a fit-out;
• you’re committing to a longer term; or
• you have limited ability to relocate (because you’re a destination business or rely on a specific catchment area).

It’s also worth thinking ahead about your ability to assign or sublease if your business changes direction. A clear, well-structured lease can make that much easier to navigate.

And if you’re comparing premises, don’t just compare the headline rent. Compare:

• the rent review method (CPI vs fixed vs market);
• the outgoings; and
• the term and option structure.

How To Negotiate A CPI Rent Review Clause (Practical Tips For Small Businesses)

Rent review clauses are negotiable more often than many business owners realise, especially if you’re:

• signing a longer lease term;
• a strong tenant (good trading history, established brand, good references);
• taking on a premises that has been vacant; or
• agreeing to invest in upgrades or fit-out works.

Here are practical negotiation points we often see landlords and tenants discuss.

1) Clarify The CPI Index And Review Date Mechanics

If the lease doesn’t clearly define CPI and the calculation, you can end up with different interpretations later.

At a minimum, you want certainty about:

• which CPI series applies; and
• which quarter’s figure will be used for each review.

2) Consider A Cap (Especially For Longer Terms)

As a tenant, a cap can be a reasonable request to protect cashflow in unusual inflation periods.

As a landlord, you can sometimes agree to a cap if the deal structure otherwise works (for example, a longer term, stronger security, or a market review later).

3) Watch Out For “CPI Or X%, Whichever Is Greater”

This drafting changes the bargain. If CPI is low for several years, you still pay the minimum increase.

If the landlord wants certainty, you may be able to negotiate a lower fixed minimum, or restructure reviews (for example, CPI annually and market review at option time).

4) Align The Rent Review Method With Your Business Model

Different businesses tolerate rent increases differently. A CPI rent review might be manageable if:

• you have recurring customers and can adjust pricing regularly; or
• your revenue typically moves with inflation.

But if you’re locked into long-term fixed customer pricing, or you operate on narrow margins (common in hospitality and retail), you may want more protection or predictability.

5) Get The Whole Lease Looked At, Not Just The Rent Review Clause

Even a “fair” CPI clause can feel unfair if the rest of the lease is one-sided (for example, broad outgoings recovery, strict make-good obligations, or unclear repair obligations).

If you’re unsure, it can help to have the entire deal reviewed so your risks are clear before you commit. Depending on your scenario, you might also need help with documents connected to your premises arrangements, like a Property Licence Agreement if the arrangement is more of a flexible licence than a traditional lease.

Common Questions About CPI Rent Reviews

Is CPI Rent Review Better Than A Fixed Increase?

It depends on the numbers and your risk tolerance.

If inflation stays low, CPI may be lower than a fixed 4–5% increase, which helps tenants. But if inflation spikes, CPI can exceed a typical fixed increase, which benefits landlords (unless there is a cap).

The “best” option is the one that matches your business’s ability to absorb increases, and the deal you’ve negotiated overall (term, incentives, outgoings, make-good, and flexibility).

Can A CPI Rent Review Be Challenged?

Usually, CPI reviews are mechanical: if the clause is clear and the CPI figure is published, it’s hard to dispute the outcome.

Disputes usually arise because:

• the clause is unclear (which CPI series, which quarter, what formula);
• the landlord applied the wrong numbers; or
• the lease has conflicting rent review clauses.

If you think a CPI increase has been calculated incorrectly, it’s worth raising it early and checking the lease wording carefully.

Does CPI Apply To Outgoings Too?

Not automatically.

Outgoings are usually recovered based on actual costs, estimates, or specific escalation rules set out in the lease. They’re separate from rent, and a CPI clause for rent won’t necessarily control how outgoings change.

This is one reason tenants should read the outgoings clauses closely and understand what you’re really agreeing to pay beyond base rent.

Does A CPI Rent Review Affect GST?

Rent is often subject to GST if the landlord is registered for GST (which is common for commercial premises). If the rent increases, the GST payable on rent typically increases proportionately.

This is general information only and not tax advice - speak to your accountant or tax adviser about how GST applies to your lease.

Key Takeaways

• A CPI rent review adjusts rent in line with inflation, using CPI figures published by the ABS.
• How CPI is defined in the lease matters (which CPI series, which quarter, and the exact calculation formula).
• Tenants should watch for CPI “floors” (minimum increases), “caps” (maximum increases), and ratchet drafting that prevents rent from ever decreasing.
• Landlords should aim for clear, administrable CPI clauses to reduce disputes and ensure the lease remains a reliable investment document.
• Rent review terms are often negotiable, especially when balanced with lease term, incentives, fit-out contributions, and option structures.
• It’s usually worth reviewing the whole lease, not just the rent review clause, because outgoings, repair obligations, and make-good can significantly affect the real cost of the premises.

If you’d like help reviewing or negotiating a commercial lease (including the rent review clause), you can reach us at 1800 730 617 or team@sprintlaw.com.au for a free, no-obligations chat.