Define boundaries before preparing the file
A batch check submits normalized numbers to assess apparent WhatsApp registration, unusable records and format errors. Confirm lawful provenance, the business step the result supports, and whether countries or channels require separate batches. Without this scope, a file may upload successfully but produce unusable outputs.
Treat each import as a work unit with a name, creation time and owner, and retain the protected source under the approved retention policy. This makes disputes and batch comparisons traceable.
Fields and format
Use separate country-code and national-number fields or one consistently normalized international number. Do not mix plus-prefixed and local notation in one file.
Keep country code, subscriber number without local trunk prefix where applicable, and optional customer or channel reference fields that do not affect validation. Prefer a standard CSV or spreadsheet encoded as UTF-8.
Prevent header rows being read as records, spreadsheet scientific notation changing long numbers, and extensions or comments appearing inside phone cells. These details cause many batch failures.
Clean, deduplicate and sample
Normalize separators and country prefixes, deduplicate by full international number, and remove impossible lengths, all-zero and test ranges.
For merged sources, decide whether to check every number for a user or only a documented primary number; the provider returns results at number level.
Pilot boundary lengths, unusual prefixes and previously failing records before full submission. A small manually reviewed sample is inexpensive insurance against a complete rerun.
Batches, fields and exceptions
Split large work by country, business line or campaign so failures can be isolated and rerun. Keep sizes manageable and avoid concentrated peak-time submissions.
Define mappings for registered, not registered, malformed and temporarily unknown and bind each to an action such as authorized SMS fallback or CRM correction.
If unknowns spike, inspect country selection, truncation and cleaning before resubmitting. Repeatedly sending the same bad data does not improve it.
Compliance and privacy
Phone numbers are personal data and may be sensitive. Confirm consent or another lawful basis, compatible purpose and internal access to full results. Do not put unnecessary identity data in filenames or notes.
For international teams, define storage region, retention and deletion. Remove intermediate files when no longer needed.
Traceable source, minimized fields and purpose-based retention make compliance part of import design rather than a final approval stamp.
