Convert NBU to SPB

A Nokia PC Suite backup cannot be restored by Samsung Kies, so moving contacts to a Samsung phone requires extracting them and saving them in Kies’s SPB phonebook format. This transfers contacts, not the complete Nokia backup.

What an NBU file contains

.nbu is Nokia’s proprietary backup format, created by Nokia PC Suite and some Nokia Suite versions. Depending on the phone and backup settings, an NBU file can contain contacts as well as messages, calendar entries, settings, and other phone data.

What an SPB file contains

.spb is a Samsung Kies phonebook file for contact records. It is useful within the Kies ecosystem, but it is not a general-purpose phone backup and cannot hold the other data from an NBU file. A .vcf vCard file is a practical intermediate format because contact software commonly supports it.

Convert contacts with desktop software

1. Make a copy of the NBU backup. Open the copy in NBUExplorer, a desktop utility for inspecting Nokia backups, and export the contacts as a .vcf file if the backup is supported. If NBUExplorer cannot read the file or export its contacts, use compatible Nokia PC Suite or Nokia Suite software to restore the contacts to a Nokia device, then export them as vCard. Avoid restoring onto a phone containing contacts you need to keep unless you have backed them up first.
2. Open the contacts area in Samsung Kies and use Contacts → Import/Export to import the .vcf file. The exact labels vary by Kies version; choose the option to import contacts from a PC or vCard file.
3. Review the imported records, then use Kies’s contacts export or save function to create an .spb file, if that Kies version offers SPB as an export format. Reopen or import the resulting file in Kies to check that it is readable.

Do not change the filename extension from .nbu to .spb; the formats have different internal structures. If your Kies version cannot export SPB, use a VCF-to-SPB converter only if it explicitly supports Samsung phonebook files; an ordinary file renaming or generic format converter will not produce a valid SPB file.

Compatibility and data limits

The process transfers contact records only. Some fields may not map between Nokia and Samsung software, so check names, numbers, email addresses, and other important details after import. NBUExplorer, Nokia PC Suite, Nokia Suite, and older Kies releases are legacy software and may require a compatible Windows environment. Avoid uploading an NBU backup to an online converter: it can contain private data beyond contacts, and online services may not support this proprietary backup format.