Whistle
Whistle is a B2B sales development agency that supplies outsourced SDR teams and individual SDR hires to startups and scale-ups across phone, email and LinkedIn.
- Based in
- Not stated
- Founded
- 2020
- Size, as stated
- a team of over 100 people
- Ownership
- Not stated
- Pricing
- Not stated
What it does
Whistle describes itself as a global B2B sales development agency that works with startups and scale-ups to drive increased sales. Its homepage invites companies to hire its SDRs or install a full SDR department to grow B2B pipeline, with outreach, tech and analytics handled by Whistle.
Its services page set includes a fully managed outsourced SDR service, hiring individual SDRs, cold calling, data on demand, pipeline generation, RevOps for HubSpot, conference lead generation, LinkedIn outreach and cold email outreach. The outsourced service is described as covering go-to-market strategy, messaging, inbound and outbound lead generation, CRM setup, tech stack support, outreach management and reporting. The hire-SDRs offer states that SDRs launch in 5 days on 30 day terms.
In the Biteable case study, it states that 2 to 5 part-time SDRs ran an 11 month inbound campaign that scheduled 106 qualified meetings. These figures are Whistle's own claims about its work.
Whistle states that it was founded in 2020, following 3 tech exits spanning a decade in SaaS sales. It is headed by brothers David and Yonah Zeff, and its pages state that a team of over 100 people supports its services. It describes itself as a fully remote company.
Who it fits (our reading of its own pages; opinion)
From its own pages, Whistle serves startups and scale-ups that want to build B2B pipeline without building a sales development function from scratch. It states that it works with companies from early-stage startups to enterprises. Its pages describe coverage across time zones and major languages and outreach over phone, email and LinkedIn. Clients can take a fully managed SDR department or hire individual SDRs on flexible contracts. Its solutions menu lists industries including SaaS and AI, cyber security, finance, education and healthcare.
Offers it names
- Outsourced SDRA fully managed SDR team that generates pipeline for the client. Whistle states that its outsourced SDR service lets clients generate consistent pipeline without having to hire, train, or manage SDRs. It includes go-to-market strategy, messaging, inbound and outbound lead generation, CRM setup and support with tech stack, outreach management, and reporting. The team launches in 10 days.
Sources
The pages of whistle.ltd that the facts above were checked against, last on 23 Oct 2026. 31 facts in this entry were matched word for word on these pages.
- Outsourced SDRs for Fast, Predictable B2B Pipeline Growth, read 23 Oct 2026.
- Hire SDRs to Scale Your B2B Lead Generation | Whistle, read 23 Oct 2026.
- B2B Lead Generation & Outsourced SDR Services | Whistle, read 23 Oct 2026.
- About Whistle: Global Lead Generation & Sales Development Agency, read 23 Oct 2026.
- Leveraging OCR and Technical Superiority to Secure Pipeline for WNSTN | Whistle, read 23 Oct 2026.
- Validating Enterprise Sales and Accelerating Product Insights for Biteable | Whistle, read 23 Oct 2026.
Something here wrong or out of date? Send the fact and a link to the page on the agency's own site that states it through the corrections page. Agencies can also claim this entry; a claim changes no wording and no order.
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