# Shopify-pet · Day 3 — The phone-format step Klaviyo cares about

**Subject:** The phone-format step Klaviyo cares about
**Send:** Day 3
**Goal:** deepen feature understanding around the format standardizer

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Hi {{first_name}},

The single biggest source of "Klaviyo dropped this customer silently" is phone formatting. DataTools fixes this in one tool — the **format standardizer** — but the *settings* matter.

Klaviyo (and basically every modern SMS platform) wants phones in **E.164** format: `+` then country code then number, no spaces, no dashes, no extension. Like: `+14155550143`.

Three settings in DataTools' format standardizer that get this right:

**1. Set "Phone output format" to `E.164`.** Default is `national` (`(415) 555-0143`) — fine for display, broken for Klaviyo. Change it once; the preset remembers.

**2. Set "Default country" per row, not per file.** This is the non-obvious one. For each customer:
- If the `country` field has a value (e.g., "Canada", "CA", "Canadá"), use it.
- If blank, fall back to the country in the *shipping address*.
- If still blank, fall back to the file-level default (you set this — typically your store's primary market).

DataTools does this automatically when you check "Use per-row country detection". *Skip this and ~30% of international customers will end up with US country codes prepended to their numbers — which Klaviyo accepts but routes wrong, and your SMS never arrives.*

**3. Set "Quarantine un-parseable phones" to ON.** Don't drop them silently; don't pass them to Klaviyo broken. Send them to `<filename>.quarantine.csv` so you can fix the worst 10-20 by hand and re-include them.

The combination — E.164 + per-row country + quarantine — typically takes a Shopify export from "60-70% of phones survive Klaviyo's import" to "97-99%". On a 10,000-customer list, that's 2,500 - 3,500 more customers reachable per campaign.

Reply if you want me to walk through these settings on a screen-share — happy to do this for any buyer in the first 30 days.

— Michael
{{support_email}}
