Joint tax debt is one of the most overlooked financial burdens when a relationship ends. Most separating couples focus on bank accounts, mortgages, and superannuation, but a liability owed to the Australian Taxation Office doesn't simply disappear because you're no longer together. The ATO holds both parties jointly and severally liable for shared tax debts, which means each of you can be pursued for the full amount, not just your share.
What "joint and several liability" actually means
When the ATO issues an assessment for a debt that arose from a jointly lodged return, or from activity conducted by a partnership or joint venture, both parties carry the full liability. The ATO doesn't split it down the middle. If your former partner disappears or refuses to pay, the ATO can pursue you alone for the entire amount. That's the practical reality of joint and several liability, and it catches a lot of people off guard.
This is distinct from a personal tax debt one partner owes individually. If your spouse accumulated a tax liability from their own income or investment, that sits with them. But any debt that arose from shared financial activity can reach you both. Get clear on which category your debt falls into before making any decisions.
How to find out what you owe
Start by logging in to your own myGov account and checking your ATO portal. Your individual tax position is visible there. For joint debts tied to a partnership or trust you operated with your spouse, you may need to contact the ATO directly or engage an accountant to pull the full picture together.
Request a tax account statement covering at least the past 5 years. Debts can accumulate quietly, especially if a business was involved. Don't assume a clean slate without checking. It's also worth reviewing whether any outstanding lodgements exist, because unfiled returns create their own liability.
As part of your broader financial separation, you should also notify the ATO and Centrelink after separation so that each partner's tax file number is correctly associated with their own affairs going forward.
Negotiating responsibility between you and your former partner
The ATO doesn't recognise your separation agreement as a reason to change who owes what. Even if you and your spouse sign a private deed stating that one person will pay a particular tax debt, the ATO remains entitled to pursue either of you. Your agreement is enforceable between the two of you in a civil sense, but it doesn't bind the ATO.
That said, a well-drafted financial separation agreement can include specific provisions about who takes responsibility for identified tax debts, and what happens if one party fails to pay. Rockwell Family Law Services can help you document these obligations in a way that gives you legal recourse against your former partner if they default.
When negotiating, consider:
- Which partner benefited most from the activity that generated the debt.
- Which partner has the income or assets to service it now.
- Whether the property settlement can offset the debt against assets allocated to the responsible party.
What the ATO will and won't do
The ATO does offer payment plans for parties who can't pay a tax debt in full. Both partners can apply independently. If you're concerned your former spouse won't meet their share, apply for your own payment plan to prevent interest and penalties accumulating on your account.
In limited circumstances, the ATO can grant a remission of interest or penalties, particularly where a third party (like a former spouse) caused the debt without your knowledge. This is not easy to obtain, and it requires you to demonstrate you weren't involved in the decision-making that led to the liability. Legal advice is strongly recommended before pursuing this path.
The ATO will not simply transfer a debt from one taxpayer to another at your request. Only a court order or a formally processed division of partnership interests can change the legal position on the ATO's records.
Tax debts and the property settlement
A joint tax debt is a liability that forms part of your shared financial pool, just like a mortgage or a personal loan. Australian family law courts take liabilities into account alongside assets when calculating each party's entitlements. If there's a significant tax debt, it reduces the net value of the pool available to divide.
It's common for one party to assume a tax debt as part of a property settlement in exchange for retaining a particular asset. This works in practice, but the documentation needs to be precise. A consent order formalised through the Federal Circuit and Family Court of Australia is the most reliable way to record these arrangements and make them enforceable.
For more detail on how liabilities flow through the settlement process, the article on how to split debts fairly when separating covers the broader framework and practical steps.
If your former partner ran a business and owes tax
Business-related tax liabilities deserve separate attention. If your former spouse ran a business as a sole trader, that debt is theirs personally. But if you were both directors of a company, or partners in a registered partnership, your exposure could be direct and substantial. Director penalty notices can be issued by the ATO to each director for unpaid PAYG withholding and GST, regardless of who actually managed the finances.
If you were a director in name only, or if you were excluded from the financial management of the business, document that now. Gather emails, bank statements, and any correspondence that shows your limited involvement. This material can support a request for the ATO to exercise discretion or form part of a compensation claim against your former spouse through the courts.
Steps to take right now
Act early. Tax debts accumulate interest at the ATO's general interest charge rate, and penalties compound. Waiting for the property settlement to resolve before addressing a tax liability gives the debt more time to grow.
Engage a tax accountant and a family lawyer at the same time. These two professionals need to work together: the accountant to quantify the liability and deal with the ATO, and the lawyer to ensure the liability is correctly reflected in your separation agreement and any court orders. Rockwell Family Law Services works with clients to coordinate exactly this kind of approach, ensuring that tax obligations are treated as a core part of the financial separation rather than an afterthought.
Separation is already complicated. A joint tax debt adds a layer that many people don't see until it arrives as a formal demand. Addressing it directly and early gives you far more control over the outcome than waiting for the ATO to contact you.