Prepaid accounts and top-ups
How do we let prepaid customers top up from any door with the balance posting in real time and the card data kept off the agent?
Make the top-up one secure screen behind every channel. Callvu identifies the prepaid line (by number and the authentication the account allows), prefills the balance, the plan, the expiry date and the stored payment tokens, presents the top-up amounts and the plan renewals with what each buys and when it expires, takes the card or voucher on a process-controlled screen the agent and the IVR recording never see, authorizes and tokenizes, posts the balance to the prepaid billing system in real time with the plan renewed where the amount covers it, and confirms to the customer with the new balance and expiry. Live at AT&T.
Live at AT&TSimpleCallvu moves: prefill, write back
Last updated November 7, 2026.
The problem today
The top-up was taken by the IVR, posted twenty minutes later, and the customer bought a second one in between.
Prepaid customers top up often and expect the balance now: in the app, through the IVR, in a store, with an agent, by voucher. Each door has its own payment path and its own posting delay; the agent takes a card by voice; the IVR records the digits; the customer who sees no balance tops up again and then asks for a refund. The economics of prepaid are the economics of the top-up.
A top-up is a payment with a product: the amount, the plan it renews, the expiry it sets, and the balance it posts. The card data has to stay out of the agent's and the IVR's environment; the posting has to be real time because the customer is waiting; the voucher has to be validated and burned once. One process behind every door makes all the doors behave the same.
A top-up that posts while the customer watches is a customer who stays prepaid.
How it runs
From the requestto the system of record.
A prepaid customer wants to top up in the app, on the website, through the IVR (which texts a link), in a store, with an agent, or with a voucher. Callvu identifies the line and prefills it.
- Customer
- Chooses the amount or the plan and pays on the secure screen or enters the voucher.
- Agent or store associate
- Starts the top-up and sees only the result.
- Callvu
- Prefills, presents, captures and tokenizes, validates vouchers, posts in real time and confirms.
Prefill the line
The prepaid line's balance, the current plan and its expiry, the add-ons, the auto-renewal status and the stored payment tokens are prefilled from the prepaid billing system, with the authentication the account allows for a third party topping up someone else's line (number only for a credit, more for a plan change).
Present the choices
The top-up amounts, the plan renewals and the add-ons are shown with what each buys, the new expiry it sets and the balance after, in plain words; the customer chooses.
Pay on the secure screen
The card details are entered on a process-controlled screen (sent by text from the IVR or the agent, or inline in the app) outside the agent's and the IVR's environment and tokenized; a voucher code is validated against the voucher system and burned once; a decline or an invalid voucher is shown with the reason and an alternative offered.
Write back and confirm
The balance posts to the prepaid billing system in real time, the plan renews and the expiry updates where the amount covers it, the confirmation with the new balance and expiry goes to the customer by text and in the app, and the agent or the IVR sees the posted balance before the interaction ends.
Where it ends: The customer topped up from whichever door they chose, the card data never reached the agent or the IVR recording, and the balance posted in real time to the prepaid billing system, the system of record, with the confirmation sent. The Decision Trace shows the choice and the authentication; the Audit Trace shows the capture (tokenized), the posting and the confirmation with time.
Runtime enforcement
What is enforcedwhile the work runs.
The regulations preloaded in Callvu Studio and the bank's own policies, applied as steps that run, not lines in a binder. A step that breaks a rule does not run, so a completed run was compliant.
The handoff
Between the front doorand the back office.
The front door
The app, the website, the IVR with a text link, a store, an agent with a link, or a voucher.
The back office
None needed for a routine top-up; the prepaid billing system posts from the payment.
The Decision Desk
- A repeated decline, a voucher flagged as already used or fraudulent, or a plan change on a line with a fraud flag goes to the prepaid desk in the Decision Desk with the line and only the allowed outcomes.
Proof
Live at AT&T.Published results only.
Each result is a published claim, with its code on agents.callvu.com, where its status, source and last verified date are kept.
AT&T Business reached 96%+ payment completion.
ATT-04 · Self-asserted · verified 2026-11-05
AT&T Business deployed a secure payment workflow to 55,000 agents in 5 weeks.
ATT-02 · Customer-attested · verified 2026-11-02
AT&T runs close to 100 processes on Callvu, including transfers of billing responsibility, port-outs, line separations, SIM changes, activations, payment arrangements, billing, prepaid and top-ups, collections, account takeover reports, authorized user changes, device financing agreements and business account onboarding.
TEL-02 · Self-asserted · verified 2026-11-05
Questions
What buyers ask next,answered plainly.
Can the IVR take the top-up?
The IVR identifies the line and texts the customer a link to the secure screen, so the card digits are never spoken or recorded; the balance posts while the customer is still on the line.
When does the balance post?
In real time to the prepaid billing system, with the plan renewed and the expiry updated, and the confirmation sent before the interaction ends.
What about vouchers?
The code is validated against the voucher system and burned once; an invalid or used code is explained with an alternative.
Related processes
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