# Heatio funding: rounds and investors

> Heatio has raised $3.5M across 2 rounds since 2023. Investors include Ascension and SyndicateRoom. Every round with its source.

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

United Kingdom · [Seed startup](https://millionrounds.com/companies)

# Who invested in *Heatio*

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

Energy

Funding summary Updated 26 Oct 2026

**$3.5M** raised across 2 rounds since 2023, from 2 sources

**$977K** Round **$2.5M** Seed

- **Latest round:** Seed, $2.5M Jun 2024
- **Step-up i:** 2.6×
- **Investors:** 2

See who backed them

## The funding story

Each circle is a round, placed by date and sized by amount. The line above is the running total.

2024

**$977K** Round

**$2.5M** Seed

- **First round:** Round, $977K
- **Biggest round:** $2.5M
- **Between rounds:** 14 months

## The rounds

- **Jun 2024** Seed **$2.5M** *2 new* [Ascension](https://millionrounds.com/fund/ascension) [SyndicateRoom](https://millionrounds.com/fund/syndicateroom) Source recorded
- **Apr 2023** Round **$977K** No investor was named in the report. Shares issued, filed with Companies House (SH01); no report of this raise yet

## Funding filed with regulators

Heatio filed 2 raises, $792K in all. Filings say how much was sold and to how many investors; they never name the investors.

- Apr 2024 **$303K** UK share allotment
- Apr 2023 **$489K** UK share allotment

## Who was in which round

The busiest backers across the latest rounds. A filled square is a round they joined; a dark one, a round they led.

**Round** 2023 **Seed** 2024 [Ascension](https://millionrounds.com/fund/ascension) [SyndicateRoom](https://millionrounds.com/fund/syndicateroom)

## Everyone who backed them

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

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

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

## Also claim to have backed them

These 2 firms list Heatio as a portfolio company on their own websites, but no report of a round names them. They are the firms' own claims, kept apart from the rounds above.

[VISION](https://millionrounds.com/fund/vision) VC firm Per its own site

[Gateway Angels](https://millionrounds.com/fund/gateway-angels) Angel network Per its own site

## Quick answers about Heatio

### Who invested in Heatio?

Heatio's investors include Ascension and SyndicateRoom.

### How much has Heatio raised?

Heatio has raised $3.5M across 2 rounds since 2023.

### When did Heatio last raise?

Heatio's most recent round was a Seed of $2.5M in Jun 2024.

### What was Heatio's biggest round?

Its most recent round, $2.5M in Jun 2024, is also its largest on record.

### Who backed Heatio first?

Heatio's first round on record, in Jun 2024, was backed by Ascension and SyndicateRoom.

### What stage is Heatio at?

Heatio's latest named round is a Seed, in Jun 2024.

### Where is Heatio based?

Heatio is based in the United Kingdom.

## Companies like Heatio

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

[**novosound** $8.7M · Sept 2026](https://millionrounds.com/company/novosound)[**Metris Energy** $7.5M · Sept 2026](https://millionrounds.com/company/metris-energy)[**AcouBatt** $3.0M · Sept 2026](https://millionrounds.com/company/acoubatt)[**SolarSub** $1.8M · Sept 2026](https://millionrounds.com/company/solarsub)[**Nyobolt** $155M · Aug 2026](https://millionrounds.com/company/nyobolt)[**Breathe Battery Technologies** $132M · Aug 2026](https://millionrounds.com/company/breathe-battery-technologies)

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