Dealing With Dual Conditional Contracts

Most people selling their home to buy another one hope the two transactions will line up neatly, but in practice this often means signing contracts that are conditional on each other, sometimes called dual conditional contracts or back-to-back contracts. Your purchase might be subject to your existing property selling within a set period, or your sale might be subject to you successfully securing a new home. Either way, you are managing two moving parts at once, and understanding how the conditions interact is essential before you sign anything. Getting this wrong can leave you owning two properties at once, or none at all, for a period you had not planned or budgeted for.

Why Buyers and Sellers End Up With Linked Contracts

A subject-to-sale condition in a purchase contract lets a buyer exit without penalty if their own property has not sold by an agreed date, protecting them from being contractually bound to a new purchase they cannot actually fund. Sellers sometimes accept this condition because the buyer is otherwise strong, but it does introduce uncertainty into their own settlement planning, particularly if they are relying on that sale to fund their own next purchase in turn. In a competitive market, sellers may be reluctant to accept a subject-to-sale offer at all, which is one of the reasons some buyers choose to list and sell their existing home first, accepting the inconvenience of temporary accommodation in exchange for a stronger, unconditional position when they make their next offer.

How Settlement Dates Are Coordinated

When your sale and purchase are genuinely linked, the ideal outcome is settling both on the same day, so the proceeds from your sale fund your purchase without needing bridging finance in between. Achieving this requires close coordination between your conveyancer and the conveyancers acting on your sale, your purchase, and often the parties further along the chain as well. A short buffer between the two settlements is sometimes negotiated deliberately to absorb minor delays without one falling over because of the other. Where more than two properties are linked in a chain, for example your buyer is also waiting on their own sale, the coordination task multiplies, and a delay anywhere in the chain can affect everyone else in it.

What Happens If One Side Falls Through

If your sale falls through after your purchase has become unconditional, you may find yourself contractually obliged to settle a purchase you can no longer fund from the expected proceeds, which is a genuinely stressful position. This is one of the key reasons a subject-to-sale condition, properly drafted with a clear notice mechanism, matters so much. Where a linked sale is delayed for reasons like probate rather than falling through entirely, the practical solution is often a negotiated extension rather than terminating either contract outright.

Bridging Finance as a Fallback

Some buyers manage the gap between an unconditional purchase and a slower sale using bridging finance, a short-term loan that covers the overlap until the existing property sells. This can work well but adds cost and complexity, and lenders will want confidence that the existing property is genuinely marketable at a realistic price. Anyone considering this route should speak with a mortgage broker or lender early, and the MoneySmart guidance on buying a house is a useful general starting point for thinking through the budgeting involved before you commit to either contract.

Discharging an Existing Mortgage in the Chain

Because a linked sale and purchase both need to settle cleanly, discharging your existing mortgage needs to be lodged and processed in time for your sale settlement, which then needs to occur before or simultaneously with your purchase settlement. Any delay in this chain, whether from a lender being slow to prepare a discharge or a bank's settlement team being unavailable at short notice, has a flow-on effect through the whole arrangement. Lodging the discharge request as early as your contract terms allow, rather than waiting until settlement is imminent, gives everyone involved more room to absorb an unexpected delay from the lender's side without it threatening the linked purchase.

Special Conditions Worth Getting Right

Special conditions covering timing, notice periods, and what happens if either side needs an extension should be drafted specifically for your situation, not left as generic wording. This includes clarity around whether either party can terminate if the linked transaction has not progressed by a certain date, and how a deposit is treated if that happens. Buyers relying on an off-the-plan settlement as part of the chain face their own additional timing pressure that should be addressed in the same conditions. It is also worth setting out clearly what evidence is needed to demonstrate that a linked sale has genuinely fallen through, rather than simply slowed down, since this distinction determines whether an extension or a termination right applies.

How a Conveyancer Coordinates the Chain

A conveyancer managing a linked sale and purchase keeps both files moving together, checks in regularly with the other conveyancers involved, and flags early if either transaction looks like it is drifting away from the planned date. This kind of active coordination, rather than treating the two contracts as separate matters that happen to be occurring around the same time, is usually what makes the difference between a smooth double settlement and a stressful scramble in the final week. If you are planning a residential purchase alongside a sale, raising this with your conveyancer at the outset lets them structure both contracts with that in mind from day one.