The short answer
- Price your actual number inventory and call traffic on every plan. Included allowances and billable events differ.
- For a US workload, Nimbata’s Agency rates allow a partial calculation for local numbers and answered calls; add the subscription and other charges.
- If you need a starting allowance for numbers and minutes, CallRail Lead Tracking lists both; ask for overage rates for your workload.
- Keep the old service active until numbers route correctly and historical exports have been checked.
Price one workload across each plan
Use the same inventory and traffic period for every quote. A subscription price alone cannot reveal the cost of the calls your clients receive.
For a working example, suppose an agency needs ten US local numbers and five hundred answered calls, totaling one thousand call minutes in a month. Ask each vendor to quote that workload on the plan that supports your clients, including agency rates, taxes, porting, transcription and client-level features. The example excludes transcription and other add-ons.
Nimbata’s additional charges list US Agency local numbers at $1.60 per number per month and answered calls at $0.03 each. For this example, those components total thirty-one dollars: sixteen for numbers plus fifteen for answered calls. Add the Agency subscription and any other applicable charges to get a total.
CallRail’s pricing lists Lead Tracking at $50 per month plus additional usage. It includes five numbers and 250 minutes. This example exceeds both allowances. The documentation reviewed does not prove the extra-number or extra-minute rates, so obtain those rates and the applicable billing terms before calculating a total.
WhatConverts pricing lists single-account Call Tracking at $30 per month with $30 of usage credit. Agency offers have different account and usage allowances. Include the agency plan and rates for this same inventory and call mix.
The minutes in your telephone bill may differ from the minutes used in a quote. WhatConverts billing guidance rounds each call up to a whole minute. Busy or unanswered calls that connect to its tracking number also count. Its usage credit covers incoming calls and numbers, including disabled numbers.
A total duration alone cannot reproduce per-call rounding. Give the vendor a duration distribution and the count of connected but unanswered calls. Include taxes, porting fees, transcription and client-level features in the quote.
Compare the units and controls
Choose the billing unit alongside the control you need. The same volume can consume allowances differently, and an export or number pool may matter as much as the subscription.
| Vendor | Billing unit and limit | Control or export |
|---|---|---|
| CallRail | CallRail Lead Tracking: $50/month plus usage; five numbers and 250 minutes included. | CallRail website pools: four to 300 numbers; reducing a pool requires support. |
| WhatConverts | WhatConverts Call Tracking: $30/month with $30 usage credit for a single account; agency allowances differ. | WhatConverts pools assign numbers to visitor sessions and recycle them after expiry. |
| Nimbata | Nimbata Agency US rates: $1.60 per local number/month and $0.03 per answered call, plus subscription and other charges. | Nimbata call exports use the active filters and date range, as well as selected columns. |
Source: CallRail: pricing, CallRail: decrease website pool size, WhatConverts: pricing, WhatConverts: understand Dynamic Number Pools, Nimbata: additional charges, Nimbata: exports and email reports, Nimbata: pricing
The table is a starting point for a quote, not a complete bill. The single-account WhatConverts example is not an agency quote. Check the plan needed for each client and the price of each extra number.
Nimbata’s plan comparison places dynamic number insertion on Pro, forms and CRM on Marketing, and API and webhooks on Agency. Ask which plan supports the workflow you actually intend to run.
Size the number pool for traffic
Count simultaneous visitors as well as calls when you need website attribution. A number pool temporarily assigns a tracking number to a visitor, so its size can affect whether a later call is connected to the right session.
WhatConverts explains that its dynamic number pools recycle numbers after a visitor session expires. It warns that too few numbers for concurrent sessions can leave attribution gaps. Ask how the vendor sizes the pool for your peak traffic and session duration.
CallRail’s pool guidance recommends a quarter of peak hourly traffic, with a minimum of four numbers. Its current documentation allows four to 300 numbers. That is CallRail’s sizing recommendation, not an independent accuracy guarantee.
Consider a client whose traffic rises sharply during a promotion. A pool priced for the quiet month can understate the required inventory. Include the peak period in the quote and ask how the vendor identifies a shortage.
Before shrinking a pool, identify any numbers that must remain in use. CallRail says its support team handles reductions and that removal is otherwise random unless you request the numbers to retain. Keep a record of where those numbers appear outside the website.
Move numbers and keep the history
Treat number porting and historical records as separate workstreams. A successful transfer of a phone number does not prove that past calls or recordings will appear in the new account.
CallRail’s port-away guide asks an account admin to authorize the transfer and obtain a customer service record. The receiving provider initiates the port. Keep the account active until completion, then test routing before deactivation.
WhatConverts port-out guidance requires a master account user to seek support approval before the receiving carrier initiates the request. WhatConverts port-in guidance advises keeping the existing service active until completion. Confirm account ownership and any international surcharge, and ask the destination vendor for an import sample.
Nimbata’s porting guide directs the receiving carrier to submit a port-out. For port-in, Nimbata asks for ownership evidence through support and advises keeping prior service active. Carrier fees can vary by number, so check country eligibility and charges.
Export before closing the old account and reconcile the result against the period you need. CallRail account exports can be requested by an admin month by month while the account is open. Preparation can take hours to days; check every month and the recordings separately.
Nimbata exports reflect the current filters and date range, as well as selected columns. Its server-generated downloads are single-use and expire after 24 hours. Export audio separately and check the files against the call list.
WhatConverts’ Individual Business cancellation guidance says cancellation removes the account and data. A downgrade preserves historical access but disables phone numbers. That documentation does not prove the agency-plan process, so obtain its exit terms before relying on either route.
Nimbata’s cancellation instructions warn that numbers and call data are deleted along with recordings. Its recording guidance leaves the cancellation recovery window unspecified. Get written retention terms and keep verified copies before closure.
Inspect the destination vendor’s import sample. A saved file can preserve evidence without becoming searchable call history in the replacement. Check whether identifiers and recording links still make sense to the team that will use them.
Test the quote and the handoff
Run the same exercise with each candidate and assign an owner for the old account. A written acceptance record makes the decision easier to revisit when a client or number moves.
If a vendor cannot supply a sample export, mark the missing evidence and decide who will retain access to the old account. Use the software trial to record the same acceptance criteria for each candidate.
Common questions
What is the best call tracking software for an agency?
If you need API or webhooks, Nimbata’s plan comparison places them on Agency. Compare its full quote and test the client workflow before choosing.
How much does call tracking cost for an agency?
The total depends on the plan and actual usage. CallRail Lead Tracking lists $50 per month with five numbers and 250 minutes, plus additional usage. Request a quote for your client inventory.
Do unanswered calls count toward call tracking charges?
WhatConverts billing guidance says busy or unanswered calls that connect to the tracking number count. Give each vendor your connected-call mix when requesting rates.
Can I keep my tracking numbers when I switch?
A port may be possible, subject to eligibility in your country and with your carrier. Nimbata’s porting guide directs the receiving carrier to submit port-out requests. Keep existing service active and verify routing.
Can I bring call recordings into a new platform?
Confirm the destination’s import support with a sample. CallRail’s export process lets an admin request recordings while the account is open; it does not prove compatibility with the replacement.
Sources and scope
We read the linked vendor pricing and documentation on October 29, 2026. We have not tested these products, call attribution or a migration.
Confirm current agency plan terms and country rates. Check port eligibility with each vendor. Check export completeness and destination import support before closing an account.
Source references
- Nimbata: additional charges
Checked 2026-10-29. US Agency number and call rates and other charges.
- CallRail: pricing
Checked 2026-10-29. Lead Tracking price and included usage.
- WhatConverts: pricing
Checked 2026-10-29. Single-account pricing and agency allowances.
- WhatConverts: billing FAQs
Checked 2026-10-29. Usage credit and call-minute calculation.
- CallRail: decrease website pool size
Checked 2026-10-29. Website pool size and reduction process.
- WhatConverts: understand Dynamic Number Pools
Checked 2026-10-29. Visitor-session number assignment and recycling.
- Nimbata: exports and email reports
Checked 2026-10-29. Filtered call exports and download limits.
- Nimbata: pricing
Checked 2026-10-29. Plan features and billing units.
- CallRail: port a phone number away from CallRail
Checked 2026-10-29. Port-away authorization and routing checks.
- WhatConverts: port a Number Out of WhatConverts
Checked 2026-10-29. Port-out approval and receiving carrier process.
- WhatConverts: port a Number to WhatConverts
Checked 2026-10-29. Port-in requirements and estimated timing.
- Nimbata: number porting
Checked 2026-10-29. Port-in and port-out requirements and fees.
- CallRail: exporting account-level data
Checked 2026-10-29. Account export process and preparation time.
- WhatConverts: cancel or Downgrade: Individual Business Plans
Checked 2026-10-29. Individual Business cancellation and downgrade effects.
- Nimbata: plans and billing: cancellation
Checked 2026-10-29. Cancellation and deletion of account data.
- Nimbata: call recording: retention and transcripts
Checked 2026-10-29. Recording retention and transcript behavior.