Vendor intelligence

AssemblyAI

Transcription APIs for live and recorded audio, with model-specific language and analysis options.

At a glance / documented capabilities

Read the signals. Keep the scope.

All evidence ↗

Voice

Conditional

Scope & source

YesConditional · 2026-09-28Voice Agent configured output

Source ↗

Telephony / SIP

Conditional

Scope & source

YesConditional · 2026-09-28

Source ↗

Agent tools

Verified Yes

Scope & source

YesVerified Yes · 2026-09-28

Source ↗

Integrations / webhooks

Conditional

Scope & source

YesConditional · 2026-09-28Unknown

Source ↗

Enterprise / HIPAA path

Conditional

Scope & source

YesConditional · 2026-09-28Contract-covered AssemblyAI services · Sales-confirmed agreement

Source ↗

STT

A place in your stack.

Best for

Developers selecting the recognition layer independently
Teams with both call transcription and prerecorded audio workloads

Watch-outs

A transcription hour is not a complete agent hour.
Streaming model language coverage differs from the 99-language prerecorded catalog.
Add-ons and multichannel audio change the bill.

Visit AssemblyAIOfficial site · no affiliate tracking

Pricing, with the fine printUniversal-2 async / Universal-Streaming $0.15/hour; U3.5 Pro async $0.21/hour; U3 realtime $0.45/hour; Voice Agent $0.075/min

Tracked component / plan: $0.075 / minute
V3.3 evidence review · Voice Agent API reference; standalone STT is hourly; transport/add-ons separate

All-in call price: Unknown — Complete cost cannot be established from this reference. No complete phone bill ceiling from minutes alone; carrier, model and addon scope vary.
Pricing model: component-stack
Cheapest plan: Voice Agent API reference; standalone STT is hourly; transport/add-ons separate
Free offer: $50 API credits, no credit card required
Evidence status: official
Last price check: 2026-09-28
Last product check: 2026-09-27

Billing and Pricing - AssemblyAI Set up an inbound phone agent via SIP - AssemblyAI www.assemblyai.com

Product evidence coverage

Documented claims, not tested performance.

10 / 23 fields

Product specification

What the evidence says.

Unknown means we have not established it. It does not mean No. Compliance claims require plan and contract review.

White label

UnknownUnknown after research

No supporting statement located in the bounded official corpus; confirm scope with vendor. Unknown is not No.

Source ↗Source ↗Source ↗2026-09-28

Client tenancy

UnknownUnknown after research

Billing workspace and SIP trunk domain are not evidence of agency tenant provisioning or branded customer portals.

Source ↗Source ↗2026-09-28

Client billing

UnknownUnknown after research

No supporting statement located in the bounded official corpus; confirm scope with vendor. Unknown is not No.

Source ↗Source ↗Source ↗2026-09-28

ISO 27001

Unknown

Not established by the evidence reviewed. This does not mean unsupported.

No verified source

BAA availability

DocumentedConditional

Standard BAA offered through sales; confirm covered services/configuration before PHI.

Source ↗2026-09-28

SIP

DocumentedConditional

Current SIP setup guide documents customer Twilio trunk integration; older pricing roadmap still says coming Q2 2026. Availability is documented, but rollout date and integration pricing wording need reconciliation.

Source ↗Source ↗2026-09-28

Warm transfer

UnknownUnknown after research

Tool examples mention escalation and hold execution. They do not document consultation, attended transfer, queue semantics or carrier failure recovery; conference-room audio is not conference calling.

Source ↗Source ↗2026-09-28

Cold transfer

UnknownUnknown after research

No supporting statement located in the bounded official corpus; confirm scope with vendor. Unknown is not No.

Source ↗Source ↗Source ↗2026-09-28

Batch calling

Unknown

Not established by the evidence reviewed. This does not mean unsupported.

No verified source

MCP tools

UnknownUnknown after research

Documentation MCP assists developers; it is not agent-runtime MCP. Twilio CLI is a carrier tool, not an AssemblyAI CLI.

Source ↗2026-09-28

Webhooks

DocumentedConditional

Signed lifecycle webhook posts to customer backend; customer executes business actions.

Source ↗2026-09-28

Calendar

UnknownUnknown after research

No supporting statement located in the bounded official corpus; confirm scope with vendor. Unknown is not No.

Source ↗Source ↗Source ↗2026-09-28

CRM

UnknownUnknown after research

No supporting statement located in the bounded official corpus; confirm scope with vendor. Unknown is not No.

Source ↗Source ↗Source ↗2026-09-28

Bring your carrier

DocumentedVerified Yes

Customer Twilio number/SIP trunk connects to AssemblyAI; Twilio and AssemblyAI bill separately.

Source ↗2026-09-28

Bring your model

DocumentedVerified Yes

Agent llm configuration accepts an HTTPS OpenAI-compatible endpoint or AssemblyAI LLM Gateway.

Source ↗2026-09-28

Bring your voice

UnknownUnknown after research

BYO LLM and public starter cloning do not establish BYO speech stages or voice cloning. General self-hosted models statement does not identify a TTS deployment entitlement.

Source ↗Source ↗2026-09-28

HIPAA / BAA

DocumentedConditional

Standard BAA offered through sales; confirm covered services/configuration before PHI.

Source ↗2026-09-28

SOC 2

DocumentedVendor claim

Supplier reports Type 1 and Type 2; independent reports not retrieved.

Source ↗2026-09-28

GDPR

DocumentedVendor claim

Published GDPR design statement; not independent certification or guarantee of customer compliance.

Source ↗2026-09-28

Languages

DocumentedConditional

Supported output languages use specific voices; language switching/voice matching needs configuration.

Source ↗2026-09-28

Voices

Unknown

Not established by the evidence reviewed. This does not mean unsupported.

No verified source

Realtime audio

Streaming STT

Source ↗Source ↗2026-09-27

Voice cloning

Unknown

Not established by the evidence reviewed. This does not mean unsupported.

No verified source

Architecture & connections

Understand the moving parts.

STT

AssemblyAI Universal-3.5 Pro Streaming · Universal-Streaming English/Multilingual · Universal-3.5 Pro / Universal-2 async

LLM

OpenAI · Anthropic · Google Gemini

TTS

AssemblyAI Voice Agent selected voice

TELEPHONY

Unknown — provider details not established by reviewed evidence.

Integrations

Unknown — provider details not established by reviewed evidence.

AssemblyAI pricing AssemblyAI realtime STT AssemblyAI security AssemblyAI BAA availability

Research outcomes / sources / limitations

Evidence you can inspect.

A documented feature, a supplier claim and an unanswered question are different kinds of evidence.

Buyer-relevant evidence114 / 114 applicable P0 fields researched

50 strong-source resolved · 38 unknown after research

Evidence coverage details

Strong-source resolved: 50
Vendor-claim only: 2
Conditional: 24
Other sourced outcomes: 0
Unknown after research: 38
Conflicting evidence: 0
Not applicable: 0
Not researched: 0

P1: 157 / 157 researched · Relevant P2: 27 / 27 researched.

Checked 2026-09-28. P0 means buyer-critical. Research coverage measures the work completed, not product quality, trust, or a benchmark score. A researched field can still be Unknown.

Inspect detailed evidence, sources and research gaps

September 2026 remains the historical baseline. A new research date does not mean a feature launched that day. Unknown after research and not researched are separate states.

Official documentation establishes what the supplier documents. No paid calls, independent product benchmarks or compliance audits were performed in this research pass. Coverage measures research work, never product quality.

Buyer intelligence / September 2026 baseline

The operating decision.

Price structure

Component stack

V3.3 evidence review · Voice Agent API reference; standalone STT is hourly; transport/add-ons separate

component-stackVerified Yes · 2026-09-28

STT hours/session duration, agent minutes, gateway tokens and add-ons remain distinct.

www.assemblyai.com ↗

Human fallback

Unknown — no established fallback mode

UnknownUnknown after research · 2026-09-28

No individually verified capability establishes this selection. Conditional support and vendor claims do not satisfy Strict Must-have.

Tools - AssemblyAI ↗Set up an inbound phone agent via SIP - AssemblyAI ↗www.assemblyai.com ↗streaming speech to text ↗

Documented transfer is not a staffed human service. Verify who answers, when they answer and what happens if they do not.

Try it yourself

Unknown — no independently checked public demo entry is attached.

External signals

No dated external signal in this record. Missing evidence is not a negative review.

Underlying model context: the documented stack above does not establish an exact benchmark checkpoint or its deployed settings. Public model results cannot become a AssemblyAI score.

Plan a AssemblyAI pilot See something outdated? Report a correction.Public model evidence →

Append-only price history

Every capture leaves a trace.

A new check creates a new snapshot. Deltas appear only for the same currency, unit, model and scope.

Checked datePrevious → currentDeltaEvidence

2026-09-27

No earlier captureUniversal-Streaming $0.15/hour

Tracked: $0.15 / hour · Universal-Streaming STT only

First captureAssemblyAI pricing

2026-09-28

Universal-Streaming $0.15/hourUniversal-2 async / Universal-Streaming $0.15/hour; U3.5 Pro async $0.21/hour; U3 realtime $0.45/hour; Voice Agent $0.075/min

Tracked: $0.075 / minute · V3.3 evidence review · Voice Agent API reference; standalone STT is hourly; transport/add-ons separate

Evidence improvedSet up an inbound phone agent via SIP - AssemblyAI www.assemblyai.com

2026-09-28

Universal-2 async / Universal-Streaming $0.15/hour; U3.5 Pro async $0.21/hour; U3 realtime $0.45/hour; Voice Agent $0.075/minUniversal-2 async / Universal-Streaming $0.15/hour; U3.5 Pro async $0.21/hour; U3 realtime $0.45/hour; Voice Agent $0.075/min

Tracked: $0.075 / minute · V3.3 evidence review · Voice Agent API reference; standalone STT is hourly; transport/add-ons separate

Evidence improvedSet up an inbound phone agent via SIP - AssemblyAI www.assemblyai.com

2026-09-28

Tracked: $0.075 / minute · V3.3 evidence review · Voice Agent API reference; standalone STT is hourly; transport/add-ons separate

Evidence improvedBilling and Pricing - AssemblyAI Set up an inbound phone agent via SIP - AssemblyAI www.assemblyai.com

New research observations preserve earlier captures. “Evidence improved” records what we learned; it does not claim the market changed on that date. September 2026 is the historical baseline.

Cost estimator

Price the actual workflow.

Complete cost cannot be established from this reference. No complete phone bill ceiling from minutes alone; carrier, model and addon scope vary. · Twilio carrier; optional custom/Gateway LLM; standalone STT add-ons and per-channel billing

Carry the current source into your estimate, then enter the model, voice, carrier and fixed fees your configuration needs.

Estimate AssemblyAI costs

Alternatives by category

Other stt to inspect.

Alphabetical alternatives within the same category. An editorial starting point, not a performance ranking.

DeepgramSTT

Developers comparing streaming recognition independently of an LLM

Compare

SpeechmaticsSTT

Teams testing multilingual live transcription

Compare

Evidence archive

Inspect the record.

AssemblyAI pricing2026-09-27reviewed

Universal-2 prerecorded STT is $0.15/hour. Universal-Streaming English and Multilingual are $0.15/hour; Universal-3.5 Pro Realtime is $0.45/hour. Models and add-ons have separate rates. Free access advertises up to 185 prerecorded hours and up to 333 streaming hours. Multichannel audio is billed per channel.

v2-voice-assembly-price · official · Captured 2026-09-27T02:53:32Z

Inspect official source ↗

AssemblyAI realtime STT2026-09-27reviewed

AssemblyAI offers streaming transcription for voice applications, with turn detection, prompting and speaker-related capabilities depending on model. This STT component is distinct from the separately marketed Voice Agent API.

v2-voice-assembly-product · official · Captured 2026-09-27T02:53:32Z

Inspect official source ↗

AssemblyAI security2026-09-27reviewed

AssemblyAI describes a SOC 2 Type 2 report, annual audit and configurable zero retention/training opt-out. Audit availability is vendor-stated; report scope was not independently reviewed.

v2-voice-assembly-security · vendor-claim · Captured 2026-09-27T02:53:32Z

Inspect official source ↗

AssemblyAI BAA availability2026-09-27reviewed

AssemblyAI states it can process PHI under its standard BAA; customers must contact sales to execute the agreement. Do not assume a default developer account has an executed BAA.

v2-voice-assembly-baa · vendor-claim · Captured 2026-09-27T02:53:32Z

Inspect official source ↗

Evidence describes documented scope, not a tested platform score. Unknown means a conclusion has not been established; API connectivity does not establish a native integration. Read our research methodology →

Commercial transparency

Public affiliate terms and API eligibility were not verified. No approved tracking link is on file.

Partner eligibility and commercial terms are Unknown in this review.

Visit AssemblyAIOfficial site · no affiliate tracking