What is the best speech-to-text API for financial services voice agents?

AssemblyAI is the leading choice for financial services voice agents — 43% better alphanumeric accuracy on account numbers, routing numbers, and confirmation codes versus competing STT providers, plus in-stream PII redaction and the compliance stack financial institutions require (PCI DSS v4.0, SOC 2 Type 2, ISO 27001:2022). Universal-3 Pro Streaming ($0.45/hr, unlimited concurrency) delivers ~150ms P50 latency for real-time IVR replacement and call analytics. For a fully managed conversational agent — account inquiries, balance checks, payment processing — the Voice Agent API bundles STT, LLM, and TTS over one WebSocket at $4.50/hr per session.

Does AssemblyAI integrate with existing call center platforms?

Yes. AssemblyAI offers pre-built integrations with Twilio Media Streams and Twilio SIP for telephony, plus first-party plugins for LiveKit Agents (livekit-plugins-assemblyai), Pipecat, and Vapi for cascading voice agent pipelines. For conversation intelligence in your existing contact center, AssemblyAI powers customers like EdgeTier, Aloware, CallMiner, and Observe.AI — drop Universal-3 Pro Streaming into your pipeline at $0.45/hr per stream with unlimited concurrency, and you get diarized transcripts with sentiment, entity detection, and PII redaction ready for your QA and analytics stack. For greenfield IVR replacement on an existing telephony number, the Voice Agent API ($4.50/hr) handles the full STT-LLM-TTS pipeline over one WebSocket — connect via Twilio SIP and ship in an afternoon. PCI DSS v4.0, SOC 2 Type 2, and ISO 27001:2022 certifications cover the underlying infrastructure for regulated financial workloads.

How does PII redaction work for financial services call transcription?

PII redaction runs in the streaming pipeline on final turns — enable `redact_pii: true` at connection time and the API masks PII before the transcript reaches your downstream systems (CRM, data warehouse, QA tooling, call analytics). Use `redact_pii_policies` to scope the policy set — for financial services, common policies include `credit_card_number`, `us_social_security_number`, `account_number`, `date_of_birth`, `person_name`, `phone_number`, and `email_address`. Use `redact_pii_sub` to choose between hash (####) or entity_name ([CREDIT_CARD_NUMBER]) substitution. For post-call batch workflows, the pre-recorded API also supports `redact_pii_audio: true` to generate a redacted audio file alongside the redacted transcript.

Can AI voice agents handle fraud verification and transaction disputes?

Yes. The Voice Agent API supports tool calls into your existing fraud systems and identity-verification providers — the agent can pull transaction details mid-call, run a KBA (knowledge-based authentication) check, and either resolve the dispute (initiate a provisional credit under Reg E) or escalate to a fraud investigator via Twilio SIP transfer. The full conversation transcript and detected intent are preserved through the handoff. For deeper transaction analytics or call analysis, Universal-3 Pro Streaming captures entity detection (transaction amounts, dates, merchant names) and sentiment shifts that flag a caller as a fraud-risk escalation candidate before they hang up.

Should I use the Voice Agent API or Streaming STT for my financial services platform?

It depends on how much of the stack you want to own. The Voice Agent API ($4.50/hr all-in) is the fastest path to a working IVR-replacement agent — one WebSocket handles STT, LLM, and TTS with sub-1-second end-to-end latency. Universal-3 Pro Streaming ($0.45/hr) is the right pick when you already run LiveKit, Pipecat, or Vapi and want full control over the LLM, tool calling, and core banking integrations. Both share the same Universal-3 Pro speech foundation, so transcription quality and the 43% alphanumeric accuracy gain are identical across paths.

Does AssemblyAI provide GDPR and PCI compliance features?

Yes. AssemblyAI is certified to PCI DSS v4.0 (payment card data handling), SOC 2 Type 2 (audit-grade security controls), and ISO 27001:2022 (information security management). For GDPR, EU data residency is available for streaming transcription and the LLM Gateway via dedicated regional endpoints — use the EU host to ensure customer audio and transcripts stay within the European Union. Customers can configure per-call retention and deletion policies to satisfy right-to-erasure requests. Data is encrypted with AES-128/256 at rest and TLS 1.2+ in transit. PII redaction can be enabled in-stream so sensitive fields — card numbers, SSNs, account numbers, DOBs — never reach your CRM or data warehouse. Both the Voice Agent API and Universal-3 Pro Streaming support these compliance features.

Solutions

Voice agents for financial services

Build AI voice agents that handle account inquiries, payment processing, and fraud verification — with 43% better alphanumeric accuracy for account numbers, PII redaction by default, and the compliance infrastructure financial institutions require. Ship end-to-end with our Voice Agent API, or drop Universal-3 Pro Streaming into your existing stack.

Get started free Contact sales

Account services overview

Caller verified · Account ****4532 · Priority tier

Identity

Verified

PII Redacted

Active

Stated reason for call

Disputed transaction $247.99 charge

Suggested resolution

check_circle Initiate provisional credit per Reg E timeline
check_circle Flag transaction for fraud review team

The problem

Legacy IVR is costing you customers and compliance risk

Financial services callers navigate 4-5 IVR menus before reaching a human — if they don't hang up first. Account numbers get misheard, transactions fail identity verification, and every misrouted call is a compliance exposure. Modern voice agents — built on accurate streaming STT with 43% better alphanumeric recognition, a managed LLM, and PII redaction — resolve account inquiries faster, capture sensitive data correctly, and maintain an auditable transcript of every interaction.

Built for financial services performance

Entity 43%

Better alphanumeric accuracy — account numbers, routing numbers, confirmation codes.

Latency ~150ms

P50 median streaming latency for Universal-3 Pro Streaming.

Compliance PCI

PCI DSS v4.0, SOC 2 Type 2, and ISO 27001:2022 certified.

Scale 40TB+

Audio processed daily in production.

Two ways to build

Pick the API that fits your financial services stack

Ship a working voice agent in an afternoon, or drop industry-leading STT into the platform you already run — both with PII redaction and compliance infrastructure built in.

Recommended

Voice Agent API

Our proprietary voice stack via one WebSocket. Build account inquiry agents, payment processors, and fraud verification flows with zero infra to manage.

Best for

Account inquiries, balance checks, payment processing
43% better alphanumeric accuracy for account numbers
Teams shipping fast — working agent in an afternoon
PCI DSS v4.0 and SOC 2 Type 2 certified

$4.50/hr — speech, LLM, and voice all included

Get started for free

Free tier available · No credit card required

Bring Your Own Stack

Universal-3 Pro Streaming STT API

The STT layer for your financial services voice platform. Works natively with your preferred orchestrator, compliance tooling, and core banking integrations.

Best for

Teams using LiveKit, Pipecat, or Twilio as their orchestrator
Cascading architectures (STT → LLM → TTS)
PII redaction and audio de-identification built in
Complex core banking and payment gateway integrations
High-scale deployments where margin and full control matter

$0.45/hr — transcription only, unlimited streams

View integration docs

No concurrency caps · Autoscaling included

Quickstart

Get a working agent in minutes

Voice Agent API — recommended

# Voice Agent API: financial services account inquiry agent
import asyncio, json, websockets

API_KEY = "YOUR_API_KEY"

async def run_agent():
    async with websockets.connect(
        "wss://agents.assemblyai.com/v1/ws",
        additional_headers={"Authorization": f"Bearer {API_KEY}"},
    ) as ws:
        await ws.send(json.dumps({
            "type": "session.update",
            "session": {
                "system_prompt": (
                    "You are an account services agent for First National Bank. "
                    "Verify caller identity before discussing account details. "
                    "Never read full account or card numbers aloud."
                ),
                "greeting": "Hi, this is First National — how can I help today?",
                "input": {"keyterms": ["First National", "rewards checking",
                                      "premium savings", "Reg E", "provisional credit"]},
                "output": {"voice": "ivy"},
            },
        }))
        # Stream audio in, get audio + transcript back
        async for msg in ws:
            handle(json.loads(msg))  # transcript.user, reply.audio, tool.call, ...

Universal-3 Pro Streaming + LiveKit — BYO stack

# LiveKit + AssemblyAI STT in a financial services agent pipeline
from livekit.agents import Agent, AgentSession, TurnHandlingOptions
from livekit.plugins import assemblyai, cartesia, openai, silero

class FinancialAgent(Agent):
    def __init__(self):
        super().__init__(
            instructions=(
                "You are an account services agent for First National Bank. "
                "Verify identity before disclosing account information. Be concise."
            ),
        )

async def entrypoint(ctx):
    session = AgentSession(
        stt=assemblyai.STT(
            model="u3-rt-pro",
            min_turn_silence=100,
            max_turn_silence=3000,                      # callers pause to look up accounts / read numbers
            vad_threshold=0.3,
            keyterms_prompt=["First National", "rewards checking",
                             "premium savings", "Reg E", "provisional credit"],
        ),
        llm=openai.LLM(model="gpt-4o"),
        tts=cartesia.TTS(),
        vad=silero.VAD.load(activation_threshold=0.3),
        turn_handling=TurnHandlingOptions(
            turn_detection="stt",
            endpointing={"min_delay": 0},                # avoid additive latency in STT-driven turns
        ),
    )
    await session.start(room=ctx.room, agent=FinancialAgent())

Try in Playground View full docs

Alphanumeric accuracy

43% better accuracy on account numbers, routing numbers, confirmation codes, and email addresses spoken over the phone — the data that matters most in financial services.

PII redaction & compliance

PCI DSS v4.0, SOC 2 Type 2, and ISO 27001:2022 certified. PII redaction masks card numbers, SSNs, account numbers, and DOBs before transcripts reach downstream systems.

Real-time intelligence

Sentiment analysis detects frustrated callers for priority routing. Entity detection captures transaction amounts and dates. Topic detection flags escalation triggers in real time.

Teams shipping financial voice agents on AssemblyAI

80% increase in customer satisfaction

The transcription accuracy, reliability, and speed of AssemblyAI's API have greatly enhanced our operations.

Raj Shankar, SVP Product — Calabrio

30% cost savings on real-time transcription

We require a leading edge speech-to-text provider that can meet our specialized needs: fast, accurate, targeted, and multilingual.

Super

: AssemblyAI is the leading choice for financial services voice agents — 43% better alphanumeric accuracy on account numbers, routing numbers, and confirmation codes versus competing STT providers, plus in-stream PII redaction and the compliance stack financial institutions require (PCI DSS v4.0, SOC 2 Type 2, ISO 27001:2022). Universal-3 Pro Streaming ($0.45/hr, unlimited concurrency) delivers ~150ms P50 latency for real-time IVR replacement and call analytics. For a fully managed conversational agent — account inquiries, balance checks, payment processing — the Voice Agent API bundles STT, LLM, and TTS over one WebSocket at $4.50/hr per session.
: Yes. AssemblyAI offers pre-built integrations with Twilio Media Streams and Twilio SIP for telephony, plus first-party plugins for LiveKit Agents (livekit-plugins-assemblyai), Pipecat, and Vapi for cascading voice agent pipelines. For conversation intelligence in your existing contact center, AssemblyAI powers customers like EdgeTier, Aloware, CallMiner, and Observe.AI — drop Universal-3 Pro Streaming into your pipeline at $0.45/hr per stream with unlimited concurrency, and you get diarized transcripts with sentiment, entity detection, and PII redaction ready for your QA and analytics stack. For greenfield IVR replacement on an existing telephony number, the Voice Agent API ($4.50/hr) handles the full STT-LLM-TTS pipeline over one WebSocket — connect via Twilio SIP and ship in an afternoon. PCI DSS v4.0, SOC 2 Type 2, and ISO 27001:2022 certifications cover the underlying infrastructure for regulated financial workloads.
: PII redaction runs in the streaming pipeline on final turns — enable `redact_pii: true` at connection time and the API masks PII before the transcript reaches your downstream systems (CRM, data warehouse, QA tooling, call analytics). Use `redact_pii_policies` to scope the policy set — for financial services, common policies include `credit_card_number`, `us_social_security_number`, `account_number`, `date_of_birth`, `person_name`, `phone_number`, and `email_address`. Use `redact_pii_sub` to choose between hash (####) or entity_name ([CREDIT_CARD_NUMBER]) substitution. For post-call batch workflows, the pre-recorded API also supports `redact_pii_audio: true` to generate a redacted audio file alongside the redacted transcript.
: Yes. The Voice Agent API supports tool calls into your existing fraud systems and identity-verification providers — the agent can pull transaction details mid-call, run a KBA (knowledge-based authentication) check, and either resolve the dispute (initiate a provisional credit under Reg E) or escalate to a fraud investigator via Twilio SIP transfer. The full conversation transcript and detected intent are preserved through the handoff. For deeper transaction analytics or call analysis, Universal-3 Pro Streaming captures entity detection (transaction amounts, dates, merchant names) and sentiment shifts that flag a caller as a fraud-risk escalation candidate before they hang up.
: It depends on how much of the stack you want to own. The Voice Agent API ($4.50/hr all-in) is the fastest path to a working IVR-replacement agent — one WebSocket handles STT, LLM, and TTS with sub-1-second end-to-end latency. Universal-3 Pro Streaming ($0.45/hr) is the right pick when you already run LiveKit, Pipecat, or Vapi and want full control over the LLM, tool calling, and core banking integrations. Both share the same Universal-3 Pro speech foundation, so transcription quality and the 43% alphanumeric accuracy gain are identical across paths.
: Yes. AssemblyAI is certified to PCI DSS v4.0 (payment card data handling), SOC 2 Type 2 (audit-grade security controls), and ISO 27001:2022 (information security management). For GDPR, EU data residency is available for streaming transcription and the LLM Gateway via dedicated regional endpoints — use the EU host to ensure customer audio and transcripts stay within the European Union. Customers can configure per-call retention and deletion policies to satisfy right-to-erasure requests. Data is encrypted with AES-128/256 at rest and TLS 1.2+ in transit. PII redaction can be enabled in-stream so sensitive fields — card numbers, SSNs, account numbers, DOBs — never reach your CRM or data warehouse. Both the Voice Agent API and Universal-3 Pro Streaming support these compliance features.

Build your financial services voice agent today

Free tier, no credit card. From account verification to transaction disputes in an afternoon.

Get started free