# Callback funding: rounds and investors

> Callback has raised $500K across 1 round since 2024. Investors include Y Combinator and Flybridge. Every round with its source.

Source: https://millionrounds.com/company/callback (Millionrounds; every figure on the page links to its filing or article)

United States · [Pre-seed startup](https://millionrounds.com/companies)

# Who invested in *Callback*

One round we have observed, with the 2 investors named in it. Every figure came from a named source, and where the company reported a raise to the SEC itself, that is shown beside it.

AI

Funding summary Updated 26 Oct 2026

**$500K** raised across 1 round since 2024, from 1 source

- **Latest round:** Pre-seed, $500K Sept 2024
- **Investors:** 2

See who backed them

## The rounds

- **Sept 2024** Pre-seed **$500K** [Y Combinator](https://millionrounds.com/fund/y-combinator) [Flybridge](https://millionrounds.com/fund/flybridge) Source recorded SEC filing: $2.0M sold, first sale Aug 2024

## Everyone who backed them

[Y Combinator](https://millionrounds.com/fund/y-combinator) Accelerator **1** round

[Flybridge](https://millionrounds.com/fund/flybridge) VC firm **1** round

Missing a round, or an investor who was in one? [Tell us](https://millionrounds.com/corrections?slug=callback).

## Quick answers about Callback

### Who invested in Callback?

Callback's investors include Y Combinator and Flybridge.

### How much has Callback raised?

Callback has raised $500K across 1 round since 2024.

### When did Callback last raise?

Callback's most recent round was a Pre-seed of $500K in Sept 2024.

### What was Callback's biggest round?

Its most recent round, $500K in Sept 2024, is also its largest on record.

### Who backed Callback first?

Callback's first round on record, in Sept 2024, was backed by Y Combinator and Flybridge.

### What stage is Callback at?

Callback's latest named round is a Pre-seed, in Sept 2024.

### Where is Callback based?

Callback is based in the United States.

## Companies like Callback

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