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  1. xpay✦ Commerce

  2. Directory

  3. Shopify apps

  4. Checkout - Other

  5. King Checkout Validation

King Checkout Validation

by Lightcone

5.0

(20 reviews)

67/100 · SolidBuilt for ShopifyFree plan available. Free trial available.
Best suited for stores willing to start free and move to $4/mo.

Block checkout with address validation, order limits and custom checkout rules. Use checkout validation to check shipping and billing address fields before orders are placed. Block PO boxes, require house or apartment numbers, and check postcode/ZIP, email and VAT/tax ID formats. Match phone country codes to address countries. Set order limits by cart amount, quantity or weight, with conditions for products, customer tags and countries. Use keyword, regex and field-length checks. Show localized error messages so shoppers can fix issues and continue checkout. Use checkout validation to check shipping and billing address fields before orders are placed. Block PO boxes, require house or apartment numbers, and check postcode/ZIP, email and VAT/tax ID formats. Match phone country codes to address countries. Set order limits by cart amount, quantity or weight, with conditions for products, customer tags and countries. Use keyword, regex and field-length checks. Show localized error messages so shoppers can fix issues and continue checkout. more Address validation: block PO boxes and require house or apartment numbers Set order limits by amount, quantity or weight for products and customer tags Check postcode/ZIP, email and VAT/tax ID formats with checkout field rules Match phone country codes to shipping or billing countries Build keyword, regex and field-length rules with localized error messages

Copy from the Shopify App Store listing, unedited.
View on ShopifyCompare the plansSee the scorecard
Who it’s for
Checkout - Other
What it moves
Top line

conversion rate and average order value

What it costs
From $4.99/mo

free plan available · 3 tiers

How it’s supported
67/100

Solid · from 18 reviews

What it does

Address validation: block PO boxes and require house or apartment numbers

Set order limits by amount, quantity or weight for products and customer tags

Check postcode/ZIP, email and VAT/tax ID formats with checkout field rules

Match phone country codes to shipping or billing countries

Build keyword, regex and field-length rules with localized error messages

Plan fit
What each step up actually buys you

This developer's plans are separated by features, not by how big your store is — so there is no volume that picks a tier for you. Here is what each one adds over the one below it.

Free
Free
You start with

Free for development stores

Create and test validation rules

Basic
$4.99/month
Adds

Live chat and email support

Require house, apartment or suite number

Require VAT numbers

Block PO box addresses

Premium
$9.99/month
Adds

All Basic features

Detect non-Latin characters

Set checkout field length limits

Match keywords in checkout fields

Build regular expression rules

Combine cart and customer conditions

Listed as “Free plan available. Free trial available.”. Plan contents change — confirm on the listing before you install.
Pricing
Free plan available. Free trial available.
Free

Free

Free
Free for development stores
Create and test validation rules
Basic

$4.99/month

Lowest paid plan
Live chat and email support
Require house, apartment or suite number
Require VAT numbers
Block PO box addresses
Premium

$9.99/month

All Basic features
Detect non-Latin characters
Set checkout field length limits
Match keywords in checkout fields
Build regular expression rules
Combine cart and customer conditions
Plans as listed on the Shopify App Store. Always confirm current pricing before installing.

67

/ 100
Solid
low confidence

Scored on 18 merchant reviews we hold for King Checkout Validation, across five checks. Every figure is computed from those reviews — expand any row to see the counts behind it.





Computed from the 18 reviews we hold, with 12-month windows measured to 2026-09. This scores the public review record — it is not a review of the software itself, and a low score often means we hold little evidence rather than poor evidence.
Review history
2024–2026 · 18 reviews read
Reviews per year
20242 reviews
20258 reviews
20268 reviews
What merchants say

5.0

20 reviews
5★100%
4★0%
3★0%
2★0%
1★0%
Developer replies
6%
of reviews get an answer
Reviewed at 12m+
0%
had used it a year when they wrote
From 18 reviews read. Typical reviewer had used the app for 15 days. Most merchants review in their first month, so this reflects when people write — not how long they stay.
Recent merchant reviews

The newest 8 of 20. Open one to read it in full, with the developer's reply where there is one.

The app itself is feature-rich and has been very helpful for managing shipping restrictions and preventing problematic orders. It's easy to use, flexible, and backed by a team that truly cares about its users.

Exactly what we we're looking for, since we can't use the checkout blocks as we're not on Shopify Plus.

Great support and service. Gordon is a major help!

App funktioniert wunderbar, der Support ist schnell und zielführend, haben 2 Funktionen angefragt, die innerhalb kürzester Zeit einprogrammiert wurden (Rules für billing address, war vorher nur für shipping verfügbar).

Incredible service. Had the app for 5 minutes, and needed a custom feature/rule which wasn't included. Gordon from support created my new feature within 30 min.

This app really saved us. We have an integration with SAP, and some fields have character limits that can’t be changed. This app solved that issue, and we also used it to block sending orders to certain islands via ZIP code rules — which works perfectly. I highly recommend this app. We’re running it on eight stores now.

Great app for controlling the checkout process with custom rules! We mainly use it to block specific ZIP codes and set character limits in fields before the data gets pushed to Shopify — and it works exactly as needed. What really stands out is the support team. When we first ran into an issue with ZIP code blocking, they quickly developed a new feature that supports both prefix and suffix rules. Later, when we needed to block something else, they genuinely tried to help — even though it turned out to be a limitation on Shopify’s side, not theirs. Highly recommended if you need more control over your checkout fields and top-notch support behind it.

King Checkout Validation FAQ

Answered from this app's own listing and its full review record.

Best suited for stores willing to start free and move to $4/mo.

There is a free plan, paid plans start at $4.99/month, and run to $9.99/month across 3 published tiers. Prices are as listed on the Shopify App Store and can change — confirm before installing.

King Checkout Validation's plans are separated by features rather than by store size — none of the tiers is capped on a volume you could state up front. Compare what each step adds over the one below it rather than trying to size yourself into a tier.

On our scorecard King Checkout Validation rates 67 out of 100 — solid — read from 18 merchant reviews. The developer has published replies to 1 of 18 reviews. The score reflects what the review record shows, nothing more.

20 merchants have reviewed King Checkout Validation, averaging 5.0 out of 5. We hold the review history from 2024 to 2026, which is what the year-by-year chart on this page is built from.

Quick facts
At a glance
Merchant rating

5.0 / 5 · 20 reviews


Rating, last 12 months

5.00 from 10 reviews


New reviews, last 12 months

10 (was 6)


Developer replies

1 of 18 reviews


Typical reviewer had used it

15 days


Pricing

Free plan available. Free trial available.


On the App Store since

March 15, 2024


Review history held

2024 – 2026

Integrates with
Checkout
Shopify Admin

Categories
Checkout - OtherOrder limits
Will AI shoppers find this store?

Apps like this one convert the traffic you already have. Getting recommended by ChatGPT and Perplexity is a separate problem.

Run a free readiness check
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xpay

The agent-readiness stack for the AI shopping era — helping merchants, publishers and SaaS companies get discovered, cited and transacted with by ChatGPT, Perplexity, Claude, Gemini and the custom shopping agents underneath them.

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