Built by paraplanners, for paraplanners.
A narrow suite built around two load-bearing calculations, worked to a regulator-defensible standard — and a branded compliance annex you can drop straight into a client file.
Two load-bearing calculations, and the suite around them.
Pension annual allowance — including taper, carry-forward, and MPAA — plus investment-bond chargeable-event gain with top-slicing relief. Those two are the load-bearing calculations. The rest of the suite is built around them and runs on the same engine: the lump-sum allowances, the income-tax and contribution work the pension side leans on, long-term care funding, and pension death-benefit IHT for the April 2027 regime. Most of it is published as a free calculator you can use without an account.
The boundaries are just as deliberate. No lifetime cashflow modelling — cashflow tools produce projections, we produce the figure you sign off, and the two answer different questions. No CGT, no SDLT. No general estate or trusts IHT: the inheritance-tax work stops at the pension death-benefit perimeter. No end-client portal. Narrow on purpose.
The calc engine is pure deterministic TypeScript. Every rate, threshold, and allowance lives in a versioned tax-year config; every output stamps the config version, so a calc run today is replayable to the pence six years later. AI is used only inside the extraction layer — to pull figures from uploaded PDFs (P60s, pension annual statements, chargeable-event certificates) — and every extracted field passes a user-review gate before any maths runs.
The output is an A4 compliance annex with the full statutory working, the HMRC reference for each step, your firm’s branding, and the planning disclaimer on every page, plus a single “Prepared by {name} · {date}” line. The tool version, the config version, and the source documents that fed the calc live on the calc_run audit record and the JSONL audit export — not on the page a client sees. How we verify the engine covers the HMRC corpus, the property-based tests, and the cross-LLM tripwire.
HMRC's own calculator got one rule wrong.
IPTM3820 / HMRC Agent Update 83 (2021) changed the top-slicing relief calculation for gains arising on or after 6 April 2021. The personal savings allowance and the savings-rate band must be recalculatedat the notional-income level at Step 4 of the TSR algorithm. HMRC's own published tool applied the pre-2021/22 method for a time — and spreadsheet templates and back-office calculators that copied it still do.
On the worked £90,000 offshore gain before any TAR our engine pins in CI, the pre-2021 method understates the relief by £600 — and the error grows where the gain drags the personal allowance or higher-rate thresholds into play. ParaplanAI applies the rule variant matching the gain's tax year — the Step-4 recalculation for gains from 6 April 2021, the carried-forward PSA/SRB method for earlier gains — and the annex states which variant was applied.
Worked-example basis: No time-apportioned reduction is due for any gain or policy shown. TAR is not calculated or applied. Raw gains are shown before any TAR.
The same engine handles taper-AA, carry-forward, MPAA. The pension calc is less load-bearing than top-slicing, but every paraplanner who's carried a row of £40k / £60k / £10k / £4k thresholds across four prior tax years knows the spreadsheet drifts.
UK-hosted, you control retention, no surprises.
All data is held in encrypted UK databases and processed entirely within the UK and EU. Client PII is encrypted at the application layer before storage; the calc engine never sees it. Uploaded source documents are permanently deleted 24 hours after upload; the output PDF is held alongside its calculation so it can be re-fetched.
Filed results are immutable and replayable; drafts must pass replay verification before filing. You are the controller and hold your own FCA record: delete any client, policy or calculation on demand, and finalised calculations are kept only for the window your firm sets — six years by default.
Sub-processors and the full data-processing addendum live on the trust page; the security posture and the disclosure process are on /security.
The brand is the author. The method is the proof.
ParaplanAI publishes under its own name, not a personal byline — the way an institution does. Its authority does not rest on who built it; it rests on a method anyone can check: every figure is derived by deterministic code from versioned tax-year rules, reproduced to the penny against HMRC’s own worked examples, and cited to the legislation and manual section it comes from. See how we derive and verify every figure.
The product is built and operated by working UK paraplanners at a regulated UK firm — so the rules are read by people who have carried these calculations across real client files, not just coded them. We keep names out of the headline on purpose: the credibility is in the open HMRC regression suite and the commitment to keep it current — statutory inputs confirmed within 48 hours of publication; manual and rule changes within 14 days — not a personal brand. The operator’s identity is withheld here but available to professional bodies and prospective firms on request — including a named contracting party for a sub-processor DPA.
Compliance officers and prospective firms can email info@paraplanai.co.uk for the operator’s CV, references, IFA registration verification, or a screen-share walkthrough of the calc-engine corpus run.
A calculator, not an adviser.
ParaplanAI is a calculation tool. It produces the figure and the statutory working behind it; it does not make recommendations and it does not assess suitability. The regulated adviser who uses it keeps responsibility for the advice given to the client.
Every output carries the same line: for planning and illustration purposes only; this tool does not constitute financial or tax advice.
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