Beyond a phone number
Phone appending isn't just filling in a field, it's business intelligence that supports telemarketing strategy and campaign execution. Numbers are matched and cross-checked against other database elements, mailing address, email address, so outreach timing and targeting hold up once you're on the phone.
Cold-calling a list with a low connect rate wastes rep hours dialing numbers that ring dead, are disconnected, or reach the wrong person. A 99.9% accuracy rate on appended numbers means the time your team spends dialing is time spent actually reaching prospects.
How it works
Submit your database
Send the records that need phone numbers appended, along with any existing identifiers like email or address.
Experts review it
Qualified data professionals cross-check against internal databases spanning 175+ countries.
Numbers added
Verified contact numbers are appended to matched records at 99.9% accuracy.
Final verification
The database is checked for alignment before it's delivered, typically within 4 to 5 business days.
Who uses phone appending
A sales development team building an outbound calling campaign needs working numbers before reps start dialing, not a list where a third of the calls go nowhere.
A telemarketing agency running campaigns on behalf of clients needs consistently accurate numbers to hit connect-rate targets the client is measuring them against.
An account-based marketing team coordinating multi-channel outreach needs phone numbers that line up with the email and mailing address already on file, so every touchpoint reaches the same real person.
Why it works
- 99.9% accuracy rate on appended phone numbers
- Numbers cross-checked against existing mailing address and email data
- Global coverage across the USA, Germany, Ireland, Singapore, UK, Vietnam, Canada, and more
- Supports telemarketing strategy, not just a raw number list
Before you commit
- Accuracy concerns: 99.9% accuracy is the highest guarantee across any of Data Mappers' appending services.
- Coverage concerns: numbers are available across 175+ countries, not just domestic records.
- Compliance concerns: your specific telemarketing use case, including do-not-call screening, remains your responsibility to check against local regulations.
- Bad number risk: disconnected numbers are covered by replacement or refund.
Frequently asked questions
What is the accuracy rate of your phone appending service?
The accuracy rate of Data Mappers' phone appending service is 99.9%.
What types of phone appending do you offer?
B2B phone appending, reverse phone appending, and general contact appending.
How long does phone appending take?
Turnaround depends on the size of your existing database. Our team can give you a specific timeline after reviewing a sample.
Which countries do you cover?
Coverage spans 175+ countries, including the USA, Germany, Ireland, Singapore, the UK, Vietnam, and Canada, among others.
Will the numbers work for telemarketing compliance?
Appended numbers are compiled and verified in line with Data Mappers' compliance standards, but your specific telemarketing use case, such as do-not-call list screening, remains your responsibility to check against local regulations.
What happens if a number doesn't work?
Disconnected numbers are covered. Contact Data Mappers for a replacement or refund on the affected portion of your list.
Can phone appending be combined with email appending?
Yes. Many clients append both email and phone in the same request so outreach can run across both channels from one clean file.