The short version
MaxiFi's consumption-smoothing economics are more rigorous; Boldin is far easier to live in and update. Both are US tax engines, which makes the numbers wrong rather than merely approximate for a UK household.
Why people compare them
The two most serious consumer-grade retirement planners, compared on modelling rigour versus usability.
Price and fit, side by side
| Feature | Boldin | MaxiFi Planner |
|---|---|---|
| Cheapest paid plan | BoldinFree tier, then $144 per year | MaxiFi Planner$109 per year |
| Free tier | BoldinYes | MaxiFi PlannerNo |
| Billed in pounds | BoldinNo | MaxiFi PlannerNo |
| Best for | BoldinUS savers who want deep retirement modelling and are happy to drive it themselves | MaxiFi PlannerUS households who want a rigorous lifetime spending answer rather than a pot-size target |
Where Boldin wins
- A genuinely useful free tier that builds a real plan rather than a teaser
- Very deep modelling on the paid tier: Monte Carlo, tax projections, scenario comparison and 100-plus inputs
- The Roth conversion explorer is best in class for the US market
Where MaxiFi Planner wins
- A genuinely different method: it solves for the living standard you can sustain for life rather than asking you to guess a target
- Serious tax modelling, covering federal, state and FICA taxes plus Medicare Part B IRMAA
- Optimises Social Security claiming and retirement account withdrawal order, which are the two decisions that move the numbers most
Where both fall short
- Neither models UK pensions or answers the retirement question directly.
- Neither handles ISA allowances or the tax wrapper decisions around them.
- Neither applies UK tax rules to what it shows you.
- Both are built US-first, so UK users pay in dollars and work around US assumptions.
If neither is quite right
If what you actually want is the retirement answer rather than a better dashboard, that is the gap Delphina was built for: UK pensions, ISAs and tax, projected to the age you want to stop. It does not do the job Boldin does for us savers who want deep retirement modelling and are happy to drive it themselves, so if that is the real problem, Boldin is still the better buy. Free plan is £0, no card.
Boldin vs MaxiFi Planner: common questions
Boldin is $144 per year and MaxiFi Planner is $109 per year. Compare the billing period before the number: an annual price and a monthly price are not the same thing.
You can, and some people do, because they solve different halves of the problem. It does mean paying for both, so add the two annual figures together before deciding.
Judge it on billing currency, Open Banking coverage and whether ISAs and pensions are handled. Check each one against those three points, because a tool that scores well elsewhere can still be a poor fit in the UK.
Boldin suits us savers who want deep retirement modelling and are happy to drive it themselves. MaxiFi Planner suits us households who want a rigorous lifetime spending answer rather than a pot-size target. The one that matches how you already think about money will take less setting up.
Delphina covers the gap both leave, which is UK pensions, ISAs and tax projected forward to retirement. The trade-off is that it does not do the job Boldin does for us savers who want deep retirement modelling and are happy to drive it themselves, so if that is the real need, pick one of these two.