Initial Markup (IMU) Formula
How apparel merchandisers calculate initial markup, the IMU ranges that protect margin through markdown, and why IMU is the first decision that shapes the rest of the season.
What Initial Markup measures
Initial markup is the margin baked in before the first sale. It is the percentage of the retail price that represents gross margin at full price — the starting point for every dollar of margin the season can ever deliver.
IMU % = (Retail Price − Cost) ÷ Retail Price × 100IMU is expressed as a percentage of retail, not cost. A $32 cost / $88 retail item carries a 63.6% IMU, not a 175% markup. Both numbers are correct in their own frame; the one that governs planning is the retail-basis percentage.
Worked apparel example
A DTC brand is pricing a cotton tee at $88 retail with a $32 landed cost (FOB plus freight, duty, and inbound).
IMU % = ($88 − $32) ÷ $88 = 63.6%
That 63.6% is the margin reservoir for the entire life of that SKU. Every markdown, every promotional discount, every allowance drains from it. If the season averages 15% markdowns, the final margin (MMU) lands roughly at 63.6% − (15% × some portion of units) — often 48–52% on that style.
IMU of 63.6% gives you room for markdowns and still protects margin. Healthy for DTC and full-price wholesale.
Benchmark ranges
Channel matters more than category here. Wholesale IMU is structurally lower because the retail partner takes their own margin. Luxury IMU is structurally higher because markdowns are rare. DTC falls in the middle but must carry return and shipping cost against the same IMU.
Failure modes we see
IMU treated as a styling decision, not a planning input. A designer picks a $78 ticket because it fits the brand story. The cost comes in at $34. The planner inherits a 56.4% IMU that will not survive the markdown season, and nobody flagged it until the product is already committed.
Specific patterns:
- Landed cost understated. Brands compute IMU off FOB, not landed. Freight, duty, and inbound can add 15–25% to cost — enough to move IMU from healthy to dangerous.
- Target IMU missing from the line plan. Without a target IMU per category, margin drifts style by style and nobody notices until hindsight.
- Single-channel IMU. Brands running DTC + wholesale price one ticket for both, taking an IMU hit on wholesale or leaving money on the table in DTC.
How RetailNorthstar handles IMU
In a connected system, every style carries a target IMU by channel from the moment it enters the line plan. Landed cost, ticket price, and IMU are linked — change any one and the other two update. If projected IMU drops below the category target, the style is flagged before the buy is committed.
IMU is the first decision that shapes the entire P&L for a season. Tight IMU + heavy markdown = margin collapse. Healthy IMU + disciplined markdown = plan delivered. See Maintained Markup for the full-cycle margin formula and Markdown % for the drain calculation.
Related formulas
- Maintained Markup — final margin after markdowns and allowances
- Markdown % — the drain on IMU
- Sell-Through Rate — the velocity that determines whether IMU survives
See RetailNorthstar link landed cost, ticket price, IMU target, and sell-through into one live margin view.
Book a Demo →Frequently asked about Initial Markup % (IMU)
What is the IMU formula?
IMU % = (Retail Price − Cost) ÷ Retail Price × 100. IMU is expressed as a percentage of retail price, not cost. A $32 cost / $88 retail item carries a 63.6% IMU.
What is a healthy IMU for apparel?
DTC typically targets 55–65%+; wholesale runs 50–58%+ (capped by retail-partner margin demands); luxury runs 70%+; mid-market sits around 55–62%. Category matters inside channel — fashion items often need higher IMU to absorb markdown risk.
Should IMU include freight and duty?
Yes. Landed cost — FOB plus freight, duty, inbound — is the correct input. Using FOB-only can inflate IMU by 15–25% above the real margin the style will deliver.
How is IMU different from MMU?
IMU is the planned margin at the original retail price — before any markdowns. MMU is the maintained margin after markdowns, allowances, and returns. The gap between them is the story of the season.