# Inboxbooster funding: rounds and investors

> Inboxbooster has raised $1.0M across 1 round since 2023. Investors include Y Combinator. Every round with its source.

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

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

# Who invested in *Inboxbooster*

One round we have observed, with the one investor 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.

Martech

Y Combinator: W17

Funding summary Updated 26 Oct 2026

**$1.0M** raised across 1 round since 2023, from 1 source

- **Latest round:** Pre-seed, $1.0M Apr 2023
- **Investors:** 1

See who backed them

## The rounds

- **Apr 2023** Pre-seed **$1.0M** [Y Combinator](https://millionrounds.com/fund/y-combinator) Source recorded

## Everyone who backed them

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

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

## Quick answers about Inboxbooster

### Who invested in Inboxbooster?

Inboxbooster's investors include Y Combinator.

### How much has Inboxbooster raised?

Inboxbooster has raised $1.0M across 1 round since 2023.

### When did Inboxbooster last raise?

Inboxbooster's most recent round was a Pre-seed of $1.0M in Apr 2023.

### What was Inboxbooster's biggest round?

Its most recent round, $1.0M in Apr 2023, is also its largest on record.

### Who backed Inboxbooster first?

Inboxbooster's first round on record, in Apr 2023, was backed by Y Combinator.

### What stage is Inboxbooster at?

Inboxbooster's latest named round is a Pre-seed, in Apr 2023.

### Where is Inboxbooster based?

Inboxbooster is based in the United States.

## Companies like Inboxbooster

In the same sector, and raised in the last eighteen months.

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