Discount & Savings Summary
Whether shopping during seasonal Black Friday sales, clearance events, or using promotional voucher codes online, calculating the final checkout price and total cash saved ensures smart consumer choices.
When retailers offer stacked discounts—such as a 25% store sale combined with an extra 10% promotional code at checkout—the secondary percentage discount applies sequentially to the already-reduced price, rather than simply adding the two percentage numbers together.
⚙️ Rules & Thresholds
- Single Percentage Discount Formula:
Final Price = Original Price × (1 - (Discount % / 100)).Money Saved = Original Price × (Discount % / 100). - Stacked Double Discount Formula:
Intermediate Price = Original Price × (1 - (Discount 1 % / 100)).Final Price = Intermediate Price × (1 - (Discount 2 % / 100)). - Why 25% + 10% DOES NOT Equal 35%:
- Taking 25% off £100 reduces the price to £75.00.
- Applying a secondary 10% code to £75.00 takes off an extra £7.50, leaving a final price of £67.50 (an effective total discount of 32.5%, not 35%).
- UK Retail Pricing Regulations: Under CMA rules, a retailer declaring a “Was £100, Now £75” sale discount must have sold the item at £100 for a reasonable continuous period prior to the sale.
📊 Practical Examples
- Original Ticket Price: £85.00
- Main Sale Discount: 25%
- Price After 25% Sale: £63.75 (£85 × 0.75)
- Extra Voucher Code Discount: 10% (takes 10% off £63.75)
- Extra Money Saved by Code: £6.38
Final Price You Pay: **£57.37**
Total Money Saved: £85.00 - £57.37 = **£27.63**
Effective Combined Discount: 32.5% overall saving.
📑 Common Pitfalls
- Assuming Percentage Discounts Are Additive: Adding 20% + 30% does not give 50% off; sequential stacked discounting results in a 44% total saving.
- Falling for Fake “Was/Now” Price Inflation: Some un-reputable online stores temporarily inflate original list prices immediately before launching a “50% off” campaign.
- Ignoring Delivery Fees: A 20% discount on a £15 item (£3 saved) can be entirely offset by paying a £4.99 standard delivery charge at checkout!
❓ Frequently Asked Questions (FAQ)
Stacked percentage discounts apply sequentially. The primary sale discount reduces the original ticket price first. Then, the secondary promo code discount is calculated on that new reduced price, rather than the original list price.
To find the percentage discount applied between an original price and a sale price, use the formula: `((Original Price - Sale Price) / Original Price) × 100`. For example, if a £50 item is reduced to £35: `((£50 - £35) / £50) × 100 = 30% discount`.
Under Trading Standards and CMA consumer guidance, a retailer advertising a "Was £100, Now £50" comparison must have genuinely offered the product at the higher £100 price for a meaningful continuous period (usually 28 consecutive days) prior to the price reduction.
A "3 for 2" offer gives you the cheapest item free among three selected items, representing a maximum 33.3% discount if all 3 items have identical prices. "Buy One Get One 50% Off" gives a maximum 25% discount across two identically priced items.