Chart reading
Cost of Delay Chart Explained (Start Now vs Start Later)
The chart compares two modeled paths: starting now and starting after a delay. The gap between the lines is the estimated opportunity cost of waiting under the same assumptions. Here’s how to read it safely.
Published: December 22, 2025 · Updated: December 22, 2025 · By FinToolSuite Editorial
Open the chart in the calculator
Run start-now vs start-later scenarios to see both lines on the chart.
Disclaimer
Educational purposes only; not financial advice. Charts are model outputs based on assumptions. Real outcomes vary and investments can go down as well as up. Fees, taxes, inflation, and provider rules vary.
Quick answer
- Start now line: projected value if you begin today (assumptions-based).
- Start later line: projected value if you begin after the delay window.
- The gap: start-now minus start-later at each point—an estimated cost of delay.
What the chart is showing
The x-axis is time; the y-axis is projected value under your inputs. Both lines use the same rate, horizon, and starting amount assumptions—only the start time differs. This is not a forecast.
Chart legend: start now vs start later
Start now curve
Reflects your amount, rate assumption, horizon, and compounding setting beginning immediately.
Start later curve
Uses the same assumptions but begins after the delay window. Early on it may be flat or lower because it hasn’t started compounding yet.
What the gap means
The gap at a given date is: (start-now projection) minus (start-later projection). Over longer horizons the gap may widen because the earlier start had more periods to compound under the same assumptions.
What drives the gap
- Delay length: bigger delay → usually bigger gap.
- Return assumption: higher assumptions increase sensitivity.
- Time horizon: longer horizons give differences more time to grow.
- Starting amount / contributions: larger bases create larger gaps.
- Net effects: fees, taxes, and inflation reduce what compounds.
See practical steps in the how-to guide or ready-made inputs in cost of delay examples.
Tiny walkthrough (illustrative)
Example setup: £10,000, 5% (illustrative), delay 12 months, horizon 15 years. Early on, the start-later line stays flat until it begins; over time the start-now line sits higher because it had more compounding periods. The gap is the estimated cost of waiting under these inputs.
Try this in the calculatorCommon misreads
- Reading the chart as a guarantee.
- Comparing two lines where multiple inputs changed (unfair comparison).
- Confusing the gap with profit; it’s an estimated opportunity cost under assumptions.
- Forgetting the delay is the only intended difference in a clean comparison.
FAQ
What does the gap between lines mean?
It’s the difference between the start-now and start-later projections at a point in time—an estimated cost of delay.
Why does the gap get bigger over time?
An earlier start has more periods to compound. Over longer horizons that difference can widen in the model.
Why is the start-later line flat at first?
During the delay window, the model hasn’t begun compounding the delayed scenario yet.
What if I change the rate assumption?
Higher assumptions usually increase the gap; lower assumptions reduce it. Keep rates consistent when comparing.
Can I compare multiple delays on one chart?
If you save multiple scenarios, overlays can show different delay windows. Keep other inputs the same for clarity.
Do fees, taxes, or inflation show up?
They only appear if you adjust the rate to reflect them. Otherwise the chart uses your raw assumption.
Are these results guaranteed?
No. They are estimates based on inputs. Real outcomes can be higher, lower, or negative.
How do I use saved scenarios?
Save start-now and start-later cases, then view them together to see how the lines and the gap differ over time.
Next steps
Save 2–3 scenarios (start now, start in 6 months, start in 12 months) and compare the chart overlays to see how the gap changes.