> ## Knowledge Base Index > Fetch the complete knowledge base index at: https://help.omegatheme.com/sitemap.xml > Use this file to discover available pages before exploring further. > Pure-Markdown content can be obtained by appending a '.md' suffix to the content URLs listed in the sitemap (without the trailing slash). # Overlapping zipcodes: detect and resolve zones that share a zipcode # Overlapping zipcodes: detect and resolve zones that share a zipcode When you define delivery zones by zip/postal code, the same zipcode can accidentally end up in more than one zone. DingDoong now detects these overlaps for you and lets you decide what should happen — either pick one winning zone per zipcode, or let customers choose their zone at checkout. || This feature is available on all DingDoong plans that support postal/zip code delivery zones. ## Overview If you run local delivery with multiple zones (for example "Inner city" and "Suburbs"), it's easy to list the same zipcode in two zones by mistake. When that happens, DingDoong doesn't know which zone — and which delivery rules and rates — should apply to a customer in that zipcode. The overlap check looks across all your delivery zones, flags every zipcode that appears in more than one zone, and shows you exactly which zones share it. You then choose how overlaps behave: keep one zone per zipcode (recommended for clean rates), or allow the overlap and let the customer pick. || Turning on detection changes nothing about your existing zones on its own. It only surfaces conflicts and asks you to make a choice — your zones and orders are untouched until you save a change. ## Before you start * DingDoong is installed and your delivery widget is live on your store. * Your delivery restriction is set to **Postal/zip code match** (the overlap check only applies to zip-code zones). * You have at least two delivery zones with zip/postal codes entered. ## How to find and resolve overlapping zipcodes Here's how, step by step: ### Step 1: Open your delivery zone settings In the DingDoong admin, go to your **Delivery** settings and open a zone that uses **Postal/zip code match**. This is where your zip/postal codes for the zone are listed. ![](https://storage.crisp.chat/users/helpdesk/website/-/8/3/8/3/8383e5404a31c000/image_vsspt.png) ### Step 2: Spot the flagged zipcodes Any zipcode that also exists in another zone is marked with a ⚠️ warning icon in the zip-code list. Below the list you'll see a summary such as *"3 zipcode(s) above also exist in 2 other zone(s)."* Click **Show which** to expand the list and see the exact zone names and codes that overlap. ![](https://storage.crisp.chat/users/helpdesk/website/-/8/3/8/3/8383e5404a31c000/image_1mdrw9j.png) ### Step 3: Review the overlap in Delivery restriction In the **Delivery restriction** card, when an overlap exists you'll see an **Allow overlapping zipcodes** toggle and a line like *"2 overlapping zipcode group(s) across your zones."* Click **Show details** to expand a banner for each overlapping group, listing the shared codes and the zones involved. ![](https://storage.crisp.chat/users/helpdesk/website/-/8/3/8/3/8383e5404a31c000/image_m7zhk2.png) ### Step 4: Decide how the overlap should behave Choose one of two options: * **Leave "Allow overlapping zipcodes" OFF (recommended):** Each shared zipcode is delivered by only one zone — the top-ranked one. The banner shows a warning, and you must resolve it before saving (see Step 5). * **Turn "Allow overlapping zipcodes" ON:** Customers whose zipcode sits in several zones pick their zone themselves at checkout. The banner turns informational and saving is no longer blocked. ### Step 5: Set zone priority (or remove duplicates) In each overlap banner, click **Review zone priority** (overlap off) or **Reorder zones** (overlap on) to open the priority modal. Drag zones up or down: * With overlap **off**, the top zone gets a **"Wins shared zipcodes"** badge — it's the one that delivers to those customers; the others won't. * With overlap **on**, the top zone gets a **"Shown first"** badge — this only controls the display order customers see; they still choose. Click **Save order**. Alternatively, you can simply remove the duplicate zipcode from one of the zones to clear the conflict entirely. ![](https://storage.crisp.chat/users/helpdesk/website/-/8/3/8/3/8383e5404a31c000/image_9j9dqo.png) ### Step 6: Save your settings ## How it looks on the storefront When **Allow overlapping zipcodes** is **off**, a customer entering a shared zipcode is matched to a single zone (the top-ranked one) and sees that zone's delivery options and rate — no duplicates. When it's **on**, a customer in a shared zipcode is offered the matching zones to choose from, in the priority order you set, and they select the one they want before continuing. ![](https://storage.crisp.chat/users/helpdesk/website/-/8/3/8/3/8383e5404a31c000/image_1w844y4.png) ## Common scenarios ### Two zones accidentally list the same zipcode Open the priority modal, keep **Allow overlapping zipcodes** off, and either rank the correct zone to the top so it "wins", or remove the duplicate zipcode from the zone that shouldn't have it. ### You intentionally want a zipcode in multiple zones (e.g. standard vs express) Turn **Allow overlapping zipcodes** on so customers in that zipcode can choose between the zones (for example a cheaper standard zone and a faster express zone), then use **Reorder zones** to decide which one is shown first. ### A zipcode sits in three or more zones The overlap check groups all co-occurring zones together, so a 3-way (or larger) overlap appears as a single group. Resolve it the same way — rank them in the priority modal or trim the duplicates. ## Configuration options | Option | Description | Default | Notes | | ---- | | Allow overlapping zipcodes | Lets the same zipcode stay in multiple zones. Off = one winning zone per zipcode; On = customer chooses at checkout. | Off | When off, saving is blocked until every overlap is resolved. | | Zone priority (priority modal) | The ranked order of zones in an overlap group. | Order zones were created | Off = top zone "Wins shared zipcodes". On = top zone is "Shown first" (display order only). | | Show which / Show details | Expanders that reveal the exact shared codes and zone names. | Collapsed | View-only — they don't change any settings. | The overlap check understands more than plain numbers: it matches exact codes, partial/prefix codes, numeric ranges (e.g. `1000:2000`), and UK postcodes, so a code is flagged even if two zones express it differently. ## Tips & Best practices || Keep **Allow overlapping zipcodes** off unless you truly want customers to choose between zones — one zone per zipcode keeps your rates predictable and avoids surprises at checkout. | Use **Show which / Show details** before changing anything, so you can see exactly which zones and codes collide. | If an overlap is a mistake, removing the duplicate zipcode from one zone is usually cleaner than relying on priority ranking. ## Troubleshooting ### I can't save my delivery settings — what's blocking it? Some zipcodes belong to more than one zone while **Allow overlapping zipcodes** is off. Either turn the toggle on, or open the priority banner / zip-code list and remove the duplicates, then save again. ### The warning icon stays on a zipcode after I edited a zone The check reflects your unsaved edits live. If a code is still flagged, it genuinely still exists in another zone — expand **Show which** to find where, and remove or re-rank it. ### I turned overlap on but customers still only see one zone Make sure you saved the settings, and that the customer's zipcode actually falls into more than one zone. A zipcode only shows a choice when it's part of a detected overlap group. ## FAQ ### Does enabling the overlap check change my existing zones or orders? No. Detection only surfaces conflicts and asks you to choose. Nothing changes until you save a priority order, toggle overlap, or remove a code. ### How do I undo a change? Turn **Allow overlapping zipcodes** back off (or on) to revert your choice, re-open the priority modal to restore the previous order, or re-add a zipcode you removed. Then save. ### What decides which zone "wins" when overlap is off? The top-ranked zone in the priority modal for that overlap group. Reorder it any time to change the winner.