Glossary
Cost of Delay Glossary (Quick Definitions)
A quick reference for terms you’ll see in the Cost of Delay Calculator and guides, with plain-English definitions, mini examples, and links to learn more.
Published: December 22, 2025 · Updated: December 22, 2025 · By FinToolSuite Editorial
Open the calculator
Test start-now vs start-later after you skim the definitions.
Disclaimer
Educational purposes only; not financial advice. Examples are illustrative; real returns vary and investments can go down as well as up. Fees, taxes, inflation, and rules vary by country/provider.
Quick answer
- “Cost of delay” is the estimated gap between starting now and starting later under the same assumptions.
- “Return assumption” is an input for modeling, not a promise.
Glossary
Cost of delay
Estimated difference between starting now vs starting later with the same inputs. Learn more: definition.
Mini example: Waiting 12 months removes 12 months of modeled growth.
Opportunity cost
What you give up by choosing one option over another. In this context, the growth forgone by waiting. Related: opportunity cost explainer.
Delay window
The period you wait before starting. The calculator compares start-now vs start-after-window.
Mini example: A 6-month delay means no compounding for six months in the delayed case.
Time horizon
The total length of time you are modeling (e.g., 10 or 20 years). Keep it consistent when comparing scenarios.
Return assumption
A rate you input to model growth. It’s not guaranteed. See return assumption guide.
Mini example: 5% input means £10,000 grows as if earning 5% annually in the model.
Nominal vs real
Nominal ignores inflation; real adjusts for it. Related: inflation and cost of delay.
Inflation
The general rise in prices; reduces purchasing power over time. You can test a lower “real” rate to approximate inflation.
Net return (after fees/taxes)
An approximation of what remains after costs; can be modeled by using a lower rate input. No country-specific rules included.
Fees (fee drag)
Ongoing costs that reduce growth. You can model them by lowering the rate assumption to see net effects.
Tax drag
Taxes can reduce net growth; rules vary. Model with a lower net rate if you want a conservative view.
Scenario
A saved set of inputs (e.g., start now vs start in 12 months) you can compare side-by-side in the calculator.
Compounding
Growth on growth over time. The calculator uses your rate and timeline to model this.
Mini example: £10,000 at 5% for 1 year → £10,500; the next year, 5% applies to £10,500.
Sensitivity
How much results change when inputs (rate, delay, amount, horizon) change. Use low/base/high scenarios to see sensitivity.
Where to read next
FAQ
Is cost of delay guaranteed?
No. It’s a modeled estimate based on your inputs; real outcomes can differ.
What’s the difference between nominal and real?
Nominal ignores inflation; real adjusts for it. Use a lower “real” rate to approximate after inflation.
How should I pick a return assumption?
Test low/base/high scenarios. Keep the same assumptions when comparing start dates.
Do fees and taxes matter?
Yes. They reduce net outcomes. Model with a lower net rate if you want a conservative view.
Are the charts predictions?
No. They’re illustrations based on your assumptions. Real results can be higher, lower, or negative.
Can I compare multiple delays?
Yes. Save scenarios (e.g., start now, +6 months, +12 months) and view them together.
Final CTA
Open the calculator and test two scenarios: start now vs start in 12 months. Keep inputs the same to see the modeled gap.