Who builds CrestCast

My name is Luke Walsh. I am the founder and the only developer. The forecasting engine, the app, this website and the posts on it are all mine, which means there is one person to hold to account for any figure on any of them.

I am a chartered accountant, BSc ACA PgDip: a member of Chartered Accountants Ireland, with a degree in accounting and a postgraduate diploma in software development. My working life has been Big 4 accounting and then finance inside private companies, including private equity backed ones, building the planning and forecasting systems those companies run on. That world calls it enterprise performance management, and it is the same discipline CrestCast applies to a household.

That is why the product is shaped the way it is. CrestCast produces a profit and loss, a cashflow and a balance sheet that tie to one another, and lets a household hold two versions of a plan side by side and read the difference. That is ordinary practice in a company finance department and rare in personal finance software. The UK tax, benefit and threshold rates behind the calculators and the forecast I maintain myself against gov.uk. The longer version, including the renovation that started it, is on the homepage.

I am based in Belfast, in Northern Ireland, and CrestCast is built for UK households: UK income tax, National Insurance, student loan plans and benefit rates, with the differences between England, Scotland, Wales and Northern Ireland modelled where they matter.

CrestCast is not a company. I run it as a sole trader, so there is no company number and no registered office, because there is no company to have either. If you are checking who is behind this site before linking to it or paying for it, that is the whole answer: one named person in Belfast, with the qualifications above, and nobody else.

There are no investors and no external funding, which means nobody has an interest in what CrestCast tells you except the household paying for it.

You will read “we” on most of this site. That is the ordinary voice of product copy rather than a claim about the size of the business, and it seemed better to say so here than to leave you working it out.

Any business of a reasonable size knows whether it is making money, what it is worth, and whether it can pay its bills next month, because three statements tell it so. Almost every household runs on none of that, and at best on an app that reports what was spent last month.

CrestCast projects those same three statements forward for a household, so the question can be the one actually being decided: what a bigger mortgage does, what one partner going part-time does, whether to overpay the mortgage or invest. I built it because I wanted it for my own household, and I use it for that.

The reasoning is set out in Why we built CrestCast, and the maths itself in how the forecast works.

One subscription, £7.99 a month or £79.99 a year, with a 14-day free trial. It covers the whole household, partner included. There are no tiers and no add-ons, and the price is a fixed amount rather than a percentage of what the household is worth.

There are no sponsored placements and no commissions from any product provider. CrestCast sells nothing except the subscription and makes no recommendations, so no figure in a forecast is shaped by where a fee might come from. That is the reason there is no “best buy” table anywhere on this site and no links out to lenders, brokers or platforms.

There is an affiliate programme, which pays a share of the subscription to people who recommend CrestCast. That is money going out rather than coming in, it costs the customer nothing, and it cannot reach the forecast. Full terms are on that page.

Prices and what the subscription includes are on the pricing page.

It is a forecasting tool, not a budgeting app. There is no bank connection and nothing is pulled in automatically. You enter your own figures, or paste a three column CSV that is parsed on your own device and never uploaded, and the app models what happens next rather than categorising what already happened.

The forecast horizon is a fixed ten years. Beyond a decade a household forecast stops being reliable, so CrestCast does not offer a longer one. That reasoning is set out in why we forecast ten years and not thirty.

CrestCast is a forecasting and planning tool, not regulated financial advice. Nothing in it is financial, tax, investment or legal advice. It calculates outcomes from the information you enter, and it is a planning aid rather than a substitute for professional advice. The full position is in the terms.

The calculators on this site are free, need no account and ask for no email address. They run in your browser, so the figures you type are never sent anywhere.

Your financial data is private to your own account and is never sold, never used for advertising and never handed to third parties. It is held in Postgres with row-level access control, encrypted in transit and at rest, on an independently audited platform. If you plan with a partner, you choose what to share and can turn sharing off at any time, and you can delete your account and everything in it whenever you want.

The detail, including exactly what is collected and what the site does and does not set cookies for, is in the privacy policy.

Email hello@crestcast.co.uk for anything at all, including press and anything to do with the calculators. Every address on the contact page reaches the same person.