Save the future.

Save for yours.


Save the future.

Save for yours.

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We offer the first 401(k) climate impact platform.1

The average 401(k) has 33x more emissions than the company itself. The AtmoSphere helps sustainability teams measure the financed emissions from 401(k)s, report those emissions, and learn how to work with benefits teams to reduce those emissions.

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Source: Mercer—page 8


We run a climate-friendly fund made for 401(k)s.2

The Sphere 500 Climate Fund (SPFFX) tracks the Sphere 500 Fossil-Free Index. It invests in the biggest 500 US companies, minus fossil fuel companies. We vote our shares for climate action. It's designed to check the key boxes fiduciaries look for in a 401(k) offering.

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Believe it or not,


of Americans with 401(k)s are invested in fossil fuels.3

That means


is invested in fossil fuels just through 401(k)s.

How is this possible?


Source: According to ICI, $11 trillion were invested in retirement funds as of 9/30/22. According to As You Sow, fossil fuels made up 9.34% the S&P 500 as of 6/23/23.


of Americans are worried about climate change.


didn’t know they’re investing in fossil fuels through their 401(k).


are not happy their 401(k) is invested in fossil fuels when they find out.

401(k) investments in fossil fuels

Amounts invested in fossil fuels via company 401(k)s













Together we are changing this.

For the first time, there’s a company that’s entirely focused on helping you improve your 401(k) climate impact.

It can be hard to get a climate-friendly investment option onto a 401(k) plan. The AtmoSphere platform helps sustainability teams understand how to reduce  401(k) emissions without having to change providers, and the Sphere 500 Climate Fund (SPFFX) is a climate-friendly fund option that can be added to existing retirement plans.

We created the Sphere 500 fund to offer a simple and transparent approach to sustainability that can check all the boxes that benefits teams look for when qualifying an investment fund for a 401(k) or 403(b) retirement savings plan.

We don't invest in oil & gas companies.

The first step in addressing climate change is to send a message to oil & gas companies loud and clear: no more business as usual. It’s time for the status quo to change.

We do reduce emissions.

The Sphere 500 Climate Fund has lower emissions than the S&P 500, because it excludes fossil fuel companies, which are the biggest contributor to global emissions.5

We do vote your shares for the planet.

Did you know that mutual funds vote on company shareholder proposals on your behalf? Most funds automatically vote however the board recommends. SPFFX votes for the planet.

As a company focused on helping stop climate change, Voltus needed this solution. I was excited when so many on my team signed up and even happier when they told me how easy the process was.”

Matthew Plante

President at Voltus

“A climate-friendly 401(k) option shows me my company actually cares about my views and the planet.”

Lauren Fraser

Cofounder of RightHandGreen
Formerly at Facebook and Rewiring America

“Companies around the world are making bold climate commitments. Adding Sphere is a no-brainer part of any climate plan.”

Maren Costa

Principal Design Lead at Microsoft
Cofounder of Amazon Employees for Climate Justice

The testimonials  given were not paid for, are not giving investment advice, and do not have a technical aspect of investing.

A fund that can check all the boxes.


Environmentally-friendly funds often are priced at a premium(4). SPFFX is priced 8.5x lower than most climate-friendly funds, and is more in line with standard index funds. This pricing is intended to make it appropriate for 401(k) plans.

Expense ratio comparison

Sphere 500 Climate Fund (SPFFX)


A typical climate-friendly fund

Simple to start

SPFFX is designed to be added to existing 401(k) plans, so you don't have to switch providers to offer a climate-friendly choice.

Platforms include:
See them all

Invest with

Invest with

The top 500 minus fossil fuels

SPFFX is the top 500 US companies by market capitalization, minus 86 companies. The independent non-profit As You Sow creates the list of fossil fuel, utility, and other companies that is excluded from the Sphere 500 Fossil-Free Index.

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S&P 500

417 / 500


Let your team put their money where their heart is.

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