Sublease office space: your step-by-step guide to doing it right

Subleasing can monetise surplus office space, but only if your head lease allows it. Before you talk to anyone else, pull out your lease and find the consent clause. Most commercial leases require written landlord consent before you can sublet any part of the premises, and skipping that step is the single most common way head tenants create legal exposure for themselves.

The immediate action is simple:

• Review your head lease for a subletting or assignment clause and note any consent conditions
• Open an in-principle conversation with your landlord before you market the space or negotiate with a prospective subtenant
• Get advice early. Sprintlaw and the Commonwealth’s property management framework both set out the legal groundwork, and Nicheadvisory can run the process end to end on your behalf

Key Takeaways

Subleasing office space succeeds when the head lease permits it, landlord consent is secured in writing, and the sublease is drafted to mirror head-lease obligations rather than copied from a generic template.

Table of Contents

• The office sublease process: a step-by-step workflow
• What landlords expect before granting sublease consent
• Which clauses protect the head tenant in a sublease agreement
• How to price and secure a sublease commercially
• Managing risk once the subtenant is in place
• When assignment or surrender beats subleasing
• Closing out and monitoring the sublease
• Why bring in tenant representation for a sublease
• Sources

The office sublease process: a step-by-step workflow

Subletting office space is not a real estate transaction so much as a compliance exercise wrapped around a commercial negotiation. Get the order wrong and you’ll be renegotiating with a landlord who no longer trusts your paperwork.

1. Build the business case. Work out your cost per utilised desk before you decide how much space to release. Utilisation analytics from sensors, badge data or booking systems give you defensible numbers rather than a hunch that “the third floor feels empty.”
2. Check the head lease and any applicable leasing laws. Confirm the subletting clause, the consent mechanism, and whether state retail leasing legislation applies to your premises.
3. Prepare a landlord proposal. Landlords typically want the identity of the proposed subtenant, a floor plan showing the demised area, the proposed term, and the rent and outgoings split. A concise, well-documented proposal moves faster through legal review than a vague request.
4. Negotiate commercial terms with the subtenant. Settle rent, term, security and outgoings before you draft anything.
5. Draft a bespoke sublease. Sprintlaw is explicit that a generic template is a false economy here. The sublease has to sit inside the head lease’s obligations, not alongside them.
6. Secure written landlord consent, then hand over cleanly. No verbal green light. Get it in writing, then complete a condition report and physical handover.

Pro Tip: Run your utilisation numbers and your landlord conversation in parallel, not sequentially. Landlords who see a data-backed proposal early tend to move faster than ones who get a cold call after you’ve already found a subtenant.

What landlords expect before granting sublease consent

Landlord consent is where most subleases stall, usually because the head tenant approaches it as a formality rather than a negotiation of its own. Consent clauses vary from lease to lease, but the pattern is consistent.

• Landlords generally want to see the subtenant’s financials, a permitted use statement, and a draft of the sublease itself before granting consent, and approaching them with all three ready speeds up the review
• Some landlords require a deed of covenant from the subtenant, binding them directly to the landlord on key obligations
• The sublease term must sit inside the head lease term. A sublease that could theoretically outlast the head lease will be rejected on sight
• If you’re a Commonwealth entity or dealing with one, RMG 500 sets formal endorsement and notification requirements, and expects subtenants to be charged market-consistent rent using the CNL Suite templates
• State-based retail leasing legislation can impose additional disclosure obligations if your premises falls within a retail shopping centre or similar definition

None of this is unusual. It’s just detail that has to be right the first time, because a rejected consent request resets your timeline by weeks.

Which clauses protect the head tenant in a sublease agreement

A sublease is not a shorter, simpler version of your head lease. It’s a separate document that has to mirror your obligations while adding protections a head lease never needed. The clauses that matter most:

• Parties, premises and head lease reference. Attach an area plan and expressly state the sublease is subject to, and incorporates, the head lease terms
• Term, rent and rent review. Rent review mechanics should track the head lease where possible, and the term must expire before or on the head lease expiry date
• Outgoings and GST treatment. Specify exactly what’s recoverable and how GST is applied to rent and outgoings
• Security and insurance. A bond or bank guarantee sized to realistic exposure, plus a requirement for the subtenant to hold public liability and contents insurance
• Permitted use, fitout and make-good. Lock the subtenant into the same permitted use as your head lease and require landlord and head-tenant sign off on any fitout changes
• Default and termination. Set out remedies for subtenant default, and address what happens to the sublease if the head lease itself is terminated early

Every one of these exists because a generic template assumes a straightforward two-party relationship. A sublease has three parties with interlocking interests, and the drafting needs to reflect that.

How to price and secure a sublease commercially

Rent for a sublease has to work on two levels: it needs to be commercially attractive enough to fill your surplus space quickly, and it can’t undercut your head lease obligations. Benchmark against current market conditions in your precinct rather than simply matching what you’re paying, since market rents move independently of your own lease’s fixed terms.

• Use a bank guarantee or bond sized to several months’ rent, not a token amount
• Legal costs for landlord review are usually borne by the head tenant, so budget for them upfront
• Decide early whether to pass on any unamortised fitout incentive to the subtenant or absorb it as a cost of exit
• Term length, stepped rent increases and outgoings caps are your real negotiation levers, more so than headline rent

Organisations that treat lease decisions reactively tend to leave money on the table. Advisers report that strategic planning around lease timing can deliver savings of up to 30% on total lease costs, and that same discipline applies directly to how well you price and structure a sublease.

Managing risk once the subtenant is in place

Signing the sublease isn’t the finish line. The head tenant remains liable to the landlord for the whole premises, which means your risk exposure runs for as long as the subtenant occupies the space.

1. Vet the subtenant financially before you commit, not just on their word. Trading history, references and a credit check are the minimum.
2. Mirror every material head-lease obligation into the sublease, including WHS requirements, building rules and the permitted use restriction.
3. Build enforcement mechanisms into the sublease: security drawdown rights, step-in rights, and a clear default notice process.
4. Set operational protocols for shared services, after-hours access and utilities from day one, so nobody is guessing who pays for what six months in.

A subtenant’s breach becomes your problem the moment the landlord notices it, which is exactly why the sublease needs teeth, not just good intentions.

When assignment or surrender beats subleasing

Subleasing keeps you on the hook to the landlord for the full term. If your goal is a genuine, complete exit, assignment or negotiated surrender might serve you better than subletting surplus space.

• Assignment transfers the lease outright to a new tenant, which can release you from ongoing liability if the landlord agrees to it
• Negotiated surrender ends the lease early by agreement, usually with a payment to the landlord, but it draws a hard line under your exposure
• If your business needs to exit a location entirely rather than just shed excess square metreage, these routes deserve serious consideration
• Start planning 24 to 36 months before lease expiry. Options narrow and leverage weakens the closer you get to the deadline
• Budget for legal fees, landlord consent costs and make-good obligations regardless of which exit path you choose

Closing out and monitoring the sublease

The paperwork isn’t finished when the ink dries. A clean handover protects you from disputes months down the track, and ongoing monitoring keeps the arrangement from quietly drifting off the rails.

1. Obtain the landlord’s final written consent and keep a dedicated consent file, correspondence included.
2. Complete a condition report with dated photos, record all meter readings, and hand over keys and access credentials formally.
3. Confirm the subtenant’s insurance and security are active before they move in, not after.
4. Diarise the head lease expiry, rent review dates and make-good obligations, and set a recurring check-in to monitor subtenant compliance.

Pro Tip: Store the condition report and consent file somewhere your future self, or your successor, can find in thirty seconds. Sublease disputes are won or lost on paperwork nobody thought they’d need again.

Why bring in tenant representation for a sublease

Running a sublease process alongside your day job is where things go sideways. Landlord consent gets delayed because the proposal was thin, the sublease copies a template that doesn’t reflect your head lease, or nobody checked the make-good clause until the subtenant was already asking to fit out the space differently.

Nicheadvisory works exclusively for tenants, which means the lease review, landlord negotiation and sublease drafting are all built around protecting your position rather than balancing it against a landlord’s interests. That includes benchmarking rent against real market data, structuring security so it’s actually enforceable, and managing the end-to-end advisory process from initial utilisation assessment through to final handover. The result tends to be faster consent, commercial terms that hold up, and far fewer disputes once the subtenant has moved in.

If you’re carrying surplus space and want a straight answer on whether subleasing, assignment or consolidation makes the most sense for your lease, request a lease review with Nicheadvisory before you approach your landlord.

Sources

• Commonwealth property management framework — leasing (RMG 500)
• Sublease agreement key terms and legal tips in Australia | Sprintlaw
• Optimising building utilisation: A strategy for AU offices | Footfall Australia
• How better property planning can deliver 30% savings on lease costs | ASP Advisers

Recommended

• Sydney Commercial Lease: Common Mistakes to Avoid When Choosing an Office Space (Part One) – Niche Advisory
• These are the Top Tips to Signing a New Sydney Office Lease – Niche Advisory
• Sydney Office Space: Common Mistakes to Avoid When Choosing an Office Space (Part Two) – Niche Advisory
• The End of Your Office Lease: The Essential Services – Niche Advisory