Fill rate is the most watched supply metric on Blinkit, Zepto and Swiggy Instamart. When a platform raises a purchase order (PO) for your products, it expects the full quantity to arrive at the named warehouse or dark store within the appointment window. Fill rate measures how much of that expectation you met. It is a supply-side number, distinct from the customer-facing "in-stock rate" that the platform measures on its own shelves, but the two are tightly linked: a brand that consistently short-ships POs ends up out of stock in stores, loses search visibility and eventually loses listings.
How it is calculated
The basic formula is:
Fill rate = units accepted at inwarding ÷ units on the PO × 100
Some platforms compute it in value terms (₹ accepted ÷ ₹ ordered), and most also track a line fill rate (POs or lines fulfilled in full ÷ total). Units that arrive damaged, with short shelf life, wrong barcode or after the appointment window are typically rejected and count against you.
Worked example: Zepto raises a PO for 1,200 units of a ₹120 SKU (PO value ₹1,44,000). You ship 1,000 units; 40 are rejected at the gate for a mismatched GTIN. Accepted units are 960, so unit fill rate is 960 ÷ 1,200 = 80%. In value terms you have left ₹28,800 of demand unfilled on a single PO. Repeat that across four POs a month and the store-level forecast for your SKU is revised down, which means smaller POs next month.
None of the three platforms publishes a fixed fill-rate threshold on a public help page as of September 2026. Targets are set in the brand's commercial agreement and by the category manager, and brands commonly report being asked for 90% or higher. Confirm your own target with your partner team rather than assuming a number.
What a good fill rate looks like
Above 95% is the level at which forecasts become stable and category managers start extending you to more stores. Between 85% and 95% you will usually be asked for a corrective plan. Below 85% for several consecutive cycles is where brands see POs shrink, SKUs de-prioritised or "temporarily unavailable" flags that are hard to reverse. These bands are working experience, not a published scale.
How to improve it
- Reconcile the PO the day it lands: check quantities, MRP, GTIN and expiry rules before you pick, not at the platform gate.
- Hold a safety stock of your top 20% SKUs near each platform mother warehouse so a PO never waits on production.
- Book the inwarding appointment as soon as the PO is confirmed; late arrivals are rejections, not partial credit.
- Fix master data (barcodes, case pack, dimensions) once, centrally; most gate rejections are data errors, not stock errors.
- Track fill rate per platform per warehouse weekly and share it with the category manager before they raise it with you.
Blooprint's quick commerce management service runs PO reconciliation and fill rate reporting for brands. The Blinkit, Zepto and Instamart seller guide covers the onboarding steps that come before your first PO.