ActuaPlan Update v1.2 Taxes/Payroll (Beta), What-ifs & Optimizers (Beta), UI Refresh

January 1, 2026

TLDR
• 🧾 International tax system (US / SG / DE / UK / CA) (beta, audit in progress)
• 🎛️ What-ifs, sensitivity, and safe withdrawal optimizers (beta)
• ✨ A cleaner, more modern UI

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Hi everyone,

It's been a while since the last ActuaPlan update post, but we've been working on improvements and feature enhancements non-stop! A lot have been shipped under the hood and it's finally a good time to share what's new.

1. International tax system (Beta)

ActuaPlan now includes a beta tax/payroll engine for:

• United States (US)
• Singapore (SG)
• Germany (DE)
• United Kingdom (UK)
• Canada (CA)

Tax (and payroll) systems are complicated, hence while we've made a lot of progress, we're being careful not to label this as "feature complete" yet.

That said, we've already run a number of reasonableness tests on the engine and we're so far comfortable to ship as beta.

It's also worth clarifying the intent here:

ActuaPlan is a financial modeling tool. We want taxes to be as accurate as reasonably possible, but the goal is not to replicate a perfect tax filing product. The ultimate aim, for us, is to ensure that the future projections stay realistic, especially when comparing strategies (withdrawal timing, Roth conversions, retirement age, taxable vs tax-advantaged accounts, etc.).

Below is a summary of what’s currently modeled (and what’s not yet):

US (2025 baseline)

• Simplified federal income tax + standard deduction (single / married filing jointly)
• Optional flat state income tax rate
• Employee payroll taxes (Social Security + Medicare)
• Long-term capital gains tax schedule on realized gains (used in withdrawal gross-up logic)

SG (YA2025 baseline)

• Resident income tax brackets
• Core reliefs (earned income relief + CPF relief)
• CPF contributions (employee + employer, age-banded, with wage ceiling)
• No capital gains tax (investment gains return 0 tax, as expected)

DE (2025 baseline)

• Income tax with married splitting
• Solidarity surcharge + optional church tax
• Realized capital gains tax (Abgeltungssteuer) with saver’s allowance (plus optional soli/church add-ons)
• Statutory pension modeling + partial taxation logic
• Major social insurance contributions (health / pension / unemployment / long-term care)

UK (2025 baseline)

• Income tax (incl. Personal Allowance taper) with Scotland vs rUK
• Employee pension contributions reducing taxable income
• Capital gains tax with AEA and income stacking (18% / 24%)
• Employee NIC + student loan repayments (modeled as payroll outflows)
• UK State Pension modeled and taxed as income

CA (2025 baseline)

• Federal + provincial income tax (with a “flat fallback” where detailed provincial tables aren’t implemented)
• Basic Personal Amount credit + payroll credits
• CPP/CPP2 + EI contributions (incl. self-employed handling)
• Realized capital gains via inclusion rate
• RRIF minimum withdrawals modeled and included in taxable income

Notes / caveats (beta stage)

To keep this update readable, I’ll focus on the gaps most likely to change results:

• Many parameter sets are 2025 baseline right now (brackets/thresholds aren’t automatically indexed forward yet).
• Several “real-world” regimes are not implemented yet (e.g., dividend/savings special rules, most credits/deductions, itemized deductions, AMT/NIIT equivalents, etc.).
• Some retirement-account taxation is still incomplete in certain countries (for example: in the US, traditional 401(k)/IRA distribution taxation and Social Security “taxable portion” rules are not fully wired into taxable income yet).
• Some features exist as helpers but aren’t fully integrated into the main projection flow yet (example: certain clawbacks / allowance mechanics).

Found something that looks wrong?

If you notice a tax/payroll outcome that seems off, please flag it using the Userback widget on the right side of the main web app.

You don’t have to send us your personal details. If you can describe the scenario at a high level (what looked wrong), we’ll do our best to dig deeper, reproduce it on our side, and run additional testing/research to figure out what’s going on.

2. What-ifs, sensitivity, and safe withdrawal optimizers (Pro, Beta)

Note: These tools are available in ActuaPlan Pro plan. They run a lot more simulations than a standard plan run, so we keep them part of Pro to support the compute cost and continued development. For now, we’re making them available on Free for a short period to gather feedback.

This is the one big feature that really took a lot of time to think about purpose and good UX.

What's included

• What-ifs: Compare scenarios without duplicating your whole plan (Example: "What if I retire 2 years later?", "What if expenses go up by 10%?")
• Sensitivity: sweep a range of assumptions (returns, inflation, expenses, retirement age) and see how success probability changes
• Safe withdrawal optimizers: target a success probability and let ActuaPlan search for a withdrawal level (instead of guessing)

How to run it (general flow)

• Run your simulation as usual.
• Open the What-if / Sensitivity / Optimizer panel on the hero KPI banner (top right of the web app).
• Pick a parameter to sweep (or pick an optimizer), then run. (Like the Social Security claiming-age optimizer, these runs can take longer than a normal simulation.)

Showcase 1: What-ifs

Insights

• +10% increase in spending meaninfully reduce the chance of success.
• Higher equity allocation will not help much.

Showcase 2: Sensitivity

Insights

• We're at a region where spending would have material impact on outcomes.

Showcase 3: Optimizer

Insights

• In order to have 90% success rate, we need to set our safe withdrawal rate at 3.04%.

3. Cleaner, more modern UI

This one is simple: update the UI so that ActuaPlan has more personality.

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Looking forward and feedback

Next priorities are:

• Completing a stronger tax audit so we can confidently move from 'beta' to 'shipped'
• Expand the assumption sets that you can tweak via what-ifs and sensitivity
• Continuing to enhance UX

As usual, I'm happy to receive any feedback and suggestions to further improve the tool. Please don't hesitate to contact me directly via the feedback button located at the right of the ActuaPlan app.

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