How to Use the Subscription Audit Calculator (UK)
Add every recurring payment — streaming, gym, software, delivery clubs, annual insurance add-ons — then see the true yearly cost in pounds and what those same payments could have become inside a UK ISA. The tool is an audit and an opportunity-cost illustration, not an instruction to cancel everything you enjoy.
Step-by-Step Guide
1. List your subscriptions
Use a quick-add chip for common UK services or tap Add subscription. For each line enter:
- Name and category so the breakdown is readable.
- Amount in pounds and the billing frequency (weekly, monthly, quarterly or annual). Annual plans are converted to a monthly equivalent automatically.
- Status: Keep (you use it), Review (maybe), or Cancel (you would drop it). Status drives the optional “redirect which subscriptions” filter and the saving-if-cancelled note.
2. Set the ISA what-if
- Horizon and S&S return: how long the redirected money stays invested, and the assumed annual return (7% is a long-run illustration, not a forecast).
- £20,000 cap: the 2026/27 adult ISA allowance. Contributions above the cap are treated as not paid into the ISA.
- Lifetime ISA: the first £4,000 you pay in each tax year can receive a 25% HMRC bonus (maximum £1,000). That £4,000 still counts toward the £20,000 cap. The bonus is extra.
- Cash ISA comparison: the same personal contributions at a cash rate, with no LISA bonus on that line.
- Inflation: deflates the future pot into today’s pounds so a 20-year number is easier to judge.
Compounding used: A = P(1 + r/n)nt with monthly contributions added before each month’s growth.
3. Read the results
- Monthly / annual / daily cost of the selected subscriptions.
- Spent over horizon — cash out of pocket with no growth.
- Projected invested ISA — S&S pot plus any LISA pot and bonus.
- Opportunity gain — ISA value minus cash spent.
- Allowance used — this year’s annualised spend as a share of £20,000.
2026/27 UK ISA rules used here
- Adult ISA allowance: £20,000 per tax year (6 April 2026 – 5 April 2027). Unused room does not roll over.
- Lifetime ISA: £4,000 sub-limit inside that £20,000, plus a 25% bonus. You normally need to be 18–39 to open one and can pay in until 50. A 25% charge usually applies if you withdraw for anything other than a first home (within the LISA property cap) or from age 60.
- From April 2027, Cash ISA subscriptions for under-65s are expected to be capped at £12,000, with the rest of the £20,000 still available for other ISA types. This calculator does not enforce that future Cash ISA cap; it is flagged only as context.
Common Scenarios & Examples
Scenario: Everyday UK streaming + gym stack
Goal: see whether a familiar set of subscriptions is a rounding error or a five-figure ISA gap over 20 years.
- Quick-add Netflix, Amazon Prime, Spotify and a gym membership (or use the first-visit sample list).
- Leave horizon at 20 years and S&S return at 7%, monthly compounding, allowance cap on.
- Leave Lifetime ISA and Cash ISA off for the base case.
- Read Future ISA vs cash spent, then mark the gym as Review or Cancel and switch “Redirect which subscriptions” to see the cut.
Sample stack (illustrative prices):
- Netflix £17.99 / month
- Amazon Prime £8.99 / month
- Spotify £11.99 / month
- Gym £39.99 / month
About £78.96 a month / £947.52 a year. Redirected into a S&S ISA at 7% for 20 years projects to roughly £41,000 versus about £19,000 spent — an opportunity gap of around £22,000. Your live results update if you change a price.
Scenario: Using the Lifetime ISA bonus
Goal: see the extra government bonus if the first £4,000 a year of redirected subscriptions goes into a LISA.
- Keep the same stack (or any list whose annual total is at least £4,000).
- Turn on Lifetime ISA 25% bonus.
- Compare the invested ISA figure with the bonus-off run. The first £4,000 each tax year becomes £5,000 in the LISA pot before growth.
LISA arithmetic:
£4,000 contributed + £1,000 bonus = £5,000 added to the LISA pot that year. The £4,000 still uses £4,000 of the £20,000 adult allowance. Early non-qualifying withdrawals usually cost 25%, which more than removes the bonus — so this line is only useful if you expect to keep the LISA for a first home or until 60.
Disclaimer & Limitations
Not professional advice: This calculator is an educational estimate. It is not financial, tax or investment advice. ISA rules, bonuses and property caps change. Investments can fall in value. Consult a qualified adviser if you are making a real decision.
Assumptions: Subscription prices stay constant in pounds. Contributions are treated as being made at the start of each month. Returns are a constant annual rate. The £20,000 cap (when enabled) is applied each tax year. The LISA bonus is modelled as 25% of LISA contributions up to £4,000 a year and is added as those contributions are made. The Cash ISA line uses the same personal contributions with no bonus. Inflation (when enabled) only deflates the future pot; it does not escalate subscription prices.
Not modelled: Platform fees, fund charges, tax outside an ISA, the 25% LISA withdrawal charge, the April 2027 Cash ISA cap for under-65s, Junior ISAs, or changing your subscriptions over time.