Promotional Marketing: Sales Promotion Types, Rules and ROI

In short: promotional marketing covers the temporary offers that push people to buy now (a discount, a bundle, a free gift, a sweepstakes, a sample), and in the US it is framed by FTC guides that require, among other things, that any “was” price be a genuine price you actually charged for a substantial period. Before any promotion, run one calculation: with a 40% gross margin, a 20% discount forces you to double your sales just to earn as much as before.

Sales promotion has a poor reputation because it is often used on reflex to fill a slow month. Used deliberately, it serves precise goals: getting a product tried, clearing inventory, recruiting customers, rewarding loyal ones. Here are the techniques, the rules and the method to make a promotion pay.

What is promotional marketing?

It is the set of techniques that add a short-term advantage to an offer to trigger an immediate purchase. Three traits tie them together: they are temporary, they bring a concrete benefit (price, quantity, gift, chance to win) and they aim for a fast effect on sales.

There are two audiences:

• consumers, whom you want to bring into the store or onto the site, get to try, buy more or come back;
• retailers and resellers, whom a manufacturer encourages to stock a product, give it more shelf space or order more.

A real estate agent offering a free home valuation, an accounting firm offering new businesses half off the first month, a bakery giving away the tenth loaf: the logic is the same for services and professional firms, within the ethics rules of each profession.

What are the main sales promotion techniques?

Technique	Main goal	Watch out for
Instant price discount	Speed up purchase, clear stock	Genuine reference price
Bundle or free quantity (“buy 2, get 1 free”)	Raise basket size	Customers stockpiling
Mail-in or digital rebate	Recruit without showing a lower price	Hard to predict redemption
Free sample or trial	Get a new product tried	Distribution cost
Free gift with purchase	Differentiate the offer	Conditions disclosed upfront
Sweepstakes or contest	Engagement, lead capture	No purchase necessary, official rules
Loyalty card or program	Bring customers back	Cumulative cost of rewards

The right choice depends on the goal. To introduce a product, a sample or a free trial works better than a discount, which mostly attracts people who already knew the brand. To bring customers back, perks reserved for existing customers avoid discounting to everyone, an approach covered in our article on customer retention.

Which US rules apply to promotions?

This is a summary, not legal advice. State laws add their own layer, so check the rules in the states where you sell before a large campaign.

Former price comparisons. The FTC’s Guides Against Deceptive Pricing (16 CFR 233.1) say a former price is legitimate only if it is the actual, bona fide price at which the product was offered to the public on a regular basis for a reasonably substantial period of time. Raising a price for a week so you can advertise “50% off” afterward is exactly what the guide targets. Comparisons with competitors’ prices or with a manufacturer’s suggested price are covered by separate sections of the same guides and must reflect prices actually charged in your area.

“Free” offers. The FTC’s guide on the word “free” (16 CFR 251.1) requires all conditions to be stated clearly and conspicuously at the outset, not in a footnote. The item you must buy has to be sold at its regular price. The guide also limits repetition: a “free” offer on the same product in the same area should not run more than 6 months in any 12-month period, with no more than three offers a year and at least 30 days between them.

Sweepstakes and contests. In most states, a promotion that combines a prize, chance and consideration (a required purchase or payment) is an illegal lottery. That is why US sweepstakes say “No purchase necessary” and provide a free way to enter. For mailed sweepstakes, federal law (39 U.S.C. 3001(k)) also requires stating that a purchase will not improve the chances of winning, and disclosing the rules, the sponsor, the odds and the value of each prize. Some states require registration or bonding for large sweepstakes. Contests based on skill follow different rules, but the prizes you announce must be actually awarded.

In the UK, the Chartered Trading Standards Institute’s pricing practices guidance, updated in April 2026 for the Digital Markets, Competition and Consumers Act 2024, requires reference prices to be genuine. There is no longer a fixed 28-day rule, but a “sale” price should not run longer than the higher price it is compared with.

Is a promotion profitable? The calculation to run first

A discount cuts the margin on every sale. To keep the same total margin, you have to sell more, in a proportion you can calculate:

Required volume increase = discount ÷ (gross margin − discount)

Gross margin	10% discount	20% discount	30% discount
30%	+50%	+200%	impossible
40%	+33%	+100%	+300%
50%	+25%	+67%	+150%

Example: a clothing store with a 50% margin sells 100 sweaters at $80. Total margin: $4,000. With 20% off, the sweater sells for $64 and earns $24 of margin instead of $40. The store must sell 167 sweaters to get back to $4,000, a 67% increase you can check with our percentage increase calculator. The discount calculator gives the sale price for any rate, including when two discounts stack.

This math leaves out the indirect effects: customers who would have bought at full price anyway, those who simply move up a purchase they would have made next month, and those who come for the offer and buy something else at full price. The first two reduce real profitability; the third improves it.

How do you measure the results of a promotion?

Before launch, record sales for a comparable period without a promotion. During and after, track:

• units sold and total margin, compared with the reference period;
• the number of new customers recruited, and how many come back within three months;
• sales in the following weeks, to spot the dip that follows pulled-forward purchases;
• for a sweepstakes, the number of entries and the share of usable contacts who gave consent.

The verdict is made in margin, not revenue. The general method is laid out in our article on digital marketing ROI.

What are the side effects of too many promotions?

Promotions that come too often teach customers to wait for the next deal and lower the price they consider normal for the product. The brand loses perceived value, and each campaign has to be more generous than the last to get the same effect. The FTC’s limits on repeated “free” offers reflect the same idea: a permanent promotion is no longer a promotion, it is the regular price.

A few guardrails:

• limit the number of campaigns per year and put them on a commercial calendar;
• favor added value over price cuts: a free service, an accessory, early access;
• reserve the best offers for known customers, by email or text message. Texts need prior express consent under the Telephone Consumer Protection Act, and our guide to email marketing covers the CAN-SPAM basics;
• use promotions to get people to try, for instance during a product launch, rather than to prop up a product that does not sell.

When does a promotion make sense?

A promotion is worth running when you can answer three questions before launch. What is the goal (trial, stock, recruitment, loyalty)? What volume increase does the margin math require, and is it realistic given past campaigns? How will you know, in four to eight weeks, whether it worked?

If the answer to the second question is “we would need to double sales”, choose a smaller discount, a gift with real perceived value but a low cost to you, or an offer limited to a segment of customers. The best promotions are the ones designed backward from the margin, not forward from a round number like “30% off”.