123 SA100 Solution review
A paid UK tax wizard with broad schedule support and optional tax-team review.
Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
123 SA100 Solution is web-based UK personal tax software for individuals, sole traders, landlords and other Self Assessment filers. Its step-by-step wizard prepares personal and partnership returns, supports online submission to HMRC, and covers schedules for self-employment, rental income, foreign income, non-resident circumstances and trusts. The product also lets users download, view, save and print tax returns, making it suited to filers whose circumstances extend beyond a straightforward return.
The published plans show three paid options. The Standard Package costs £18 as a one-time payment and includes a personal or partnership return, HMRC submission, a downloadable tax report and the listed specialist schedules. The Assisted Package costs £75 as a one-time payment and adds tax-advisor involvement, return review by a member of the tax team and technical support for validation issues. The Multi Returns Package costs £36 annually and covers one partnership return plus two personal returns, or any three Self Assessment returns, with website access to all forms. Account registration and preparation are available before payment, while submission is charged.
Its main strength is breadth within UK Self Assessment: the wizard brings several complex income and status scenarios into one filing workflow, while the optional review service gives users a higher-support route. Web and Android access support use across those platforms, and downloadable reports help with record keeping. Choose 123 SA100 Solution if you need support for multiple schedules or returns and want optional tax-team assistance. A simpler filing product may be a better fit for someone with a basic return who does not need these schedules or paid review.
123 SA100 Solution pros and cons
- Where it wins
- Supports self-employment, rental, foreign income, non-resident and trust schedules
- Submits personal returns online to HMRC and provides downloadable tax reports
- Assisted package includes tax-team review and validation support
- Where it doesn't
- No free plan for submission
- Assisted support costs more than the standard package
- Coverage is limited to web and Android platforms
123 SA100 Solution fact sheet, pricing and score →
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