DissoMaster Discontinued: What It Means for California Family Law and Child Support Calculations
Quick Answer: Thomson Reuters discontinued DissoMaster and the DissoMaster Suite on March 31, 2025, ending a tool that California family law courts and attorneys had relied on for decades to calculate guideline child support and spousal support. California practitioners and litigants must now use alternative support calculation software. The underlying statutory guideline formula under Family Code § 4055 has not changed, but the tool used to apply it has. Accuracy in calculation remains as critical as ever, and selecting reliable alternative software is essential.
If you have questions about child support or spousal support calculations in your California case, contact The Geller Firm at (415) 840-0570 for a confidential consultation.
What Was DissoMaster and Why Did It Matter?
DissoMaster was a proprietary software program developed specifically for California family law practice. For more than two decades, it was the standard tool used by California family law attorneys, court staff, and judges to calculate guideline child support under Family Code § 4055 and to generate proposed temporary spousal support figures during divorce proceedings.
The software's significance came from its role as the common computational reference point across California's 58 counties. When both parties' attorneys ran the same financial data through DissoMaster, the outputs served as a shared baseline for settlement negotiations, hearings, and judicial determinations. Courts trusted its calculations, attorneys understood its methodology, and litigants relied on its outputs as an objective reflection of the guideline formula.
DissoMaster's widespread adoption over decades meant that California family law had effectively standardized around a single tool. Its discontinuation, while not changing any of the underlying law, removes that standardization and requires the entire field to adapt.
Why Did Thomson Reuters Discontinue DissoMaster?
Thomson Reuters did not publicly detail its specific reasoning for discontinuing DissoMaster. However, several factors likely contributed to the decision:
Technological obsolescence. DissoMaster was built on legacy software architecture that predated modern cloud-based platforms, mobile accessibility, and integrated case management systems. Maintaining and updating older architecture to meet contemporary expectations is resource-intensive, and the product may have reached the end of its economically viable update cycle.
Market competition. The legal technology landscape has evolved significantly, with newer support calculation tools entering the market offering more intuitive interfaces, cloud accessibility, and integration with broader practice management platforms. DissoMaster faced increasing competition from alternatives that were purpose-built for a modern workflow.
Resource reallocation. Thomson Reuters, as a large legal technology company, has a broad product portfolio. Discontinuing a legacy product in favor of investing resources in higher-growth areas of the legal technology market is consistent with standard portfolio management practices.
Whatever the specific reasons, the result is the same for practitioners: a tool that was central to California family law practice for over 20 years is no longer available.
What Are the Alternatives to DissoMaster?
Several alternative support calculation programs are available to California family law practitioners following DissoMaster's discontinuation. The most widely adopted alternative is XSpouse, which was already in use by many California practitioners alongside DissoMaster and is designed to apply the same California guideline formula to produce results consistent with Family Code § 4055.
Other alternatives include various web-based support calculators and integrated family law practice management platforms that include support calculation modules. When evaluating alternatives, practitioners should consider:
Whether the software correctly implements California's guideline formula as updated by SB 343, effective September 1, 2024
Whether the software is recognized and accepted by California courts in the jurisdictions where the attorney practices
The accuracy of the software's income and deduction calculations, including the self-support reserve and proportional add-on allocation introduced by SB 343
The quality of the reporting output and whether it produces documentation suitable for submission in court proceedings
Cloud accessibility and integration with existing case management systems
The training and support resources available for transitioning practitioners
Court acceptance of specific alternative software varies by county and by individual judge. Practitioners should check with local court administrators and follow any local rules or judicial preferences regarding support calculation tools.
Does DissoMaster's Discontinuation Change California Child Support Law?
No. The discontinuation of DissoMaster affects the tool used to apply California's child support guidelines but does not alter the guidelines themselves. Family Code § 4055 and the related statutory framework continue to govern child support calculations. The same inputs, including each parent's net monthly disposable income, the custody timeshare percentage, and applicable deductions and add-ons, continue to determine the guideline support amount.
The critical point is that different software programs may produce slightly different results even when the same inputs are entered, due to differences in how they handle specific calculations, rounding, or edge cases. In a contested case, this means the parties' attorneys may present different guideline figures based on which software they used, even with identical underlying financial data. Courts will need to address how to handle such discrepancies.
Practitioners and litigants should be aware of this potential source of dispute and should be prepared to explain and defend the methodology of whichever calculation tool they use.
What Does This Mean for Existing Child Support Orders?
Existing child support orders are not affected by DissoMaster's discontinuation. Orders that were calculated using DissoMaster remain valid and enforceable as entered. The software used to calculate the original order has no bearing on its enforceability.
However, when existing orders come up for modification, the new calculation will be performed using whatever software the parties and the court now rely on. The goal is an accurate application of the statutory formula, not fidelity to any particular tool's output.
What Should Clients Expect?
For clients involved in California family law matters, DissoMaster's discontinuation is largely a behind-the-scenes development. The legal standards governing child support and spousal support have not changed. What clients should understand is:
Calculations will still be performed using software. California courts continue to use software programs to apply the guideline formula. The specific program may differ from what was used in prior proceedings, but the underlying law is the same.
Discrepancies between competing calculations may increase temporarily. As the field transitions to new tools, there may be a period during which different attorneys and courts are using different programs. This could lead to modest discrepancies in proposed support figures that will need to be addressed.
Working with an experienced attorney remains essential. The complexity of California child support calculations, amplified by the recent changes under SB 343 and the transition away from DissoMaster, makes experienced legal counsel more important than ever. An attorney who understands both the legal framework and the calculation software being used can ensure that support figures accurately reflect your financial circumstances.
Frequently Asked Questions
Will courts still accept DissoMaster outputs after March 31, 2025? DissoMaster outputs generated before the discontinuation date may have been used in proceedings close to that date, but going forward, courts expect calculations performed with current, functioning software. Using a discontinued program that cannot be updated to reflect legislative changes, such as SB 343, creates accuracy and credibility issues.
Is XSpouse fully compliant with SB 343 changes? XSpouse has been updated to incorporate the SB 343 guideline changes effective September 1, 2024, including the self-support reserve for low-income parents and the revised timeshare adjustment calculations. Practitioners should confirm that any software they use is running the current California guidelines.
Will courts specify which software they prefer? Some California courts may issue local rules or guidance on preferred support calculation software. Practitioners should monitor local court announcements and consult with court staff about any preferences or requirements in their specific jurisdiction.
Does the discontinuation affect spousal support calculations? DissoMaster was also used to generate temporary spousal support figures using the guideline formula during the pendency of divorce proceedings. Alternative programs that serve this function are available, and the same considerations regarding court acceptance and accuracy apply.
What if the other party's attorney uses a different software program? If the parties' calculations differ, the court will evaluate the methodology and inputs of each. Having a clear, defensible explanation of the software used and its compliance with current California law is important. In cases where the discrepancy is material, the court may order a unified calculation or resolve the discrepancy through testimony.
Speak With a California Family Law Attorney
The discontinuation of DissoMaster is one of several significant developments in California child and spousal support law in the past year, alongside the SB 343 guideline updates that took effect September 1, 2024. Navigating these changes requires attorneys and clients who are current on the evolving legal and technical landscape. The Geller Firm represents clients across California in child support and spousal support proceedings, modification actions, and all related family law matters.
We offer confidential virtual and in-person consultations from our Walnut Creek office.
Call (415) 840-0570 or contact us online to schedule your consultation.