Your Shipping Rates and Delivery Dates Are Managed in Two Separate Apps. That’s Where It Breaks.
Flare handles delivery dates and shipping rates in one integrated rules engine — so the date the customer picks and the rate they pay always come from the same logic, with no stitching, no drift and no manual reconciliation.
Why running dates and rates in separate apps creates a problem that compounds
You add a Saturday surcharge to your rate app — £10 extra for weekend delivery. Without Flare, the date picker doesn’t know about this rule. A customer selects Saturday, the rate app charges £10 extra, but the date picker has no awareness of Saturday’s different logic — it might still show Saturday when stock is too low, or apply the wrong cut-off. With Flare, the Saturday surcharge, the Saturday cut-off and the Saturday availability are all in one rule set. Change one thing. It updates everywhere.
Most merchants running a delivery date picker also run a separate shipping rate app. They stitch the two together — date logic in one place, rate logic in another — and hope they stay in sync. They usually don’t. A rate change that isn’t reflected in the date picker shows a date with the wrong rate. A date rule that isn’t reflected in the rate app shows a rate for a date that isn’t available. The customer sees a checkout that doesn’t quite add up.
The maintenance burden compounds over time. Every time your shipping rules change — a new carrier, a new zone, a seasonal surcharge, a promotional free delivery window — you update two systems instead of one. The update in one sometimes gets missed in the other. The mismatch is invisible until a customer notices it or an order places at the wrong rate.
The deeper problem is that dates and rates aren’t independent — they’re the same decision. Saturday delivery costs more because Saturday fulfilment costs more. Remote zones cost more because remote delivery costs more. Express delivery costs more because express handling costs more. If the logic that determines the date is separate from the logic that determines the rate, they will drift apart. Flare keeps them in the same engine so they can’t.
One rules engine for dates and rates — configured once, applied everywhere.
Date rules and rate rules live in the same engine
In Flare, the rule that determines which dates are available is the same rule that determines what rate applies. A Saturday surcharge is a single rule — it affects which days appear, what they cost, and what cut-off applies. A remote zone rule sets the transit time, the available shipping methods and the rate for that zone simultaneously. One rule. Every consequence calculated from it. No separate system to keep in sync.
Rate types — surcharges, zone-based rates, method-specific rates
Configure the full range of rate logic within Flare. Saturday and weekend surcharges — a fixed amount added when the customer selects a weekend delivery date. Zone-based rates — different pricing for Highland, Channel Islands or international zones. Method-specific rates — express delivery priced differently from standard, local delivery priced differently from national. Each rate type is configured once and applied automatically whenever the relevant date or zone is selected.
When rules change, update once — everything updates instantly
Add a new carrier to a zone. Update your Saturday surcharge for the new season. Open free delivery for a promotional period. Make the change in Flare once. The date picker, the rate shown at checkout and the shipping method available all update instantly — for every customer, on every new order, from the moment you save the change. No second system to update. No risk of one being current and the other being out of date.
Three problems that disappear when dates and rates share one engine.
Dates and rates never drift out of sync
When date logic and rate logic come from the same rules engine, they can’t contradict each other. A customer who selects Saturday sees the Saturday rate. A customer in a remote zone sees the remote rate. A customer selecting express delivery sees the express rate. The date and the rate are calculated simultaneously from the same logic — always aligned, never manually reconciled.
Rule changes update once — everywhere
One change in Flare updates the date picker, the rate shown and the available shipping methods simultaneously. No second app to update. No risk of a mismatch between what the date picker shows and what the rate app charges. Your shipping rules are as current as the last time you saved a change in Flare — for every customer, immediately.
Saturday surcharges, zone rates and method pricing — all in one place
Configure every rate type your operation needs without leaving Flare. Weekend surcharges. Remote zone pricing. Express versus standard rate differences. Promotional free delivery windows. Each rate type configured once, applied automatically whenever the relevant date, zone or method is selected at checkout.
Selling heavy furniture, freight, or oversized goods? Read our guide on Shopify shipping rules by weight and dimensions — covering custom profiles, LTL freight, and combined cart logic.
“This app works amazingly for our perishable products. Both Alex and Daniel have been amazing at setting everything up with all the complicated shipping rules and even helped build something custom for the back end. We would highly recommend this app and team for all shipping needs.”
Shipping rate automation — answered.
Separate apps have separate rule sets that drift out of sync over time. A rate change in one app isn’t automatically reflected in the other. Flare handles dates and rates in one rules engine — so the date the customer picks and the rate they pay are always calculated from the same logic. One update applies everywhere, instantly.
Yes. Set a fixed surcharge that applies automatically when a customer selects a Saturday or Sunday delivery date. The surcharge is part of the date rule — so the day, the rate and the cut-off are all configured together. When Saturday closes at its cut-off, the surcharge stops appearing. When Saturday opens again the following week, it applies automatically.
Yes. Zone-based rates are configured alongside zone-based date rules in Flare. A Highland zone with 2-day transit and Monday-to-Wednesday shipping days can also carry a different rate from a London zone with 1-day transit and Monday-to-Friday shipping. The rate applies automatically when a customer’s postcode falls within that zone — no separate rate app, no manual rate table to maintain.
Shipping rate automation is available on Precise and Pro plans, which include full rate rule configuration and carrier integration. See our pricing page for full plan details.
Replace Two Apps With One — Dates and Rates From the Same Rules Engine.
Configure your delivery dates and shipping rates in Flare once. They stay in sync automatically — no second app, no manual reconciliation, no drift between what the date picker shows and what the customer pays. Read our shipping rules guide for step-by-step setup. Or see our advanced shipping rules guide for an app comparison.
7-day free trial · Assisted setup included
Most brands are live within a day. No developer required.