Compare the same thing
Match the flight dates, route, cabin, travellers, and relevant fare conditions. For a hotel, match the room, occupancy, nights, mandatory charges, and cancellation conditions. Keep the time of the cash quote alongside the time of the award check.
Subtract the cash you still pay
For a hypothetical flight costing $1,500 in cash or 60,000 miles plus $100, the redemption value is ($1,500 − $100) ÷ 60,000, or approximately 2.33 cents per mile. This example is arithmetic, not a live offer.
If a transfer bonus changes the bank points required, calculate the bank-point value separately and include any transfer fee. Account for transfer minimums and rounding; do not assume you can transfer an arbitrary fraction of a point.
Keep currencies separate
Airline miles, hotel points, and bank points are different currencies. Display each amount separately. A combined value is meaningful only when the denominator is clearly defined, such as all points transferred from one bank program.
Ask what you would otherwise book
The same business-class itinerary may have a high cash price. That can be a valid same-cabin comparison, while a cheaper economy fare may be the alternative you would actually purchase. Show both when possible. A redemption value is a comparison, not a promise of cash profit.