This year very well may be one of the biggest years for fintech, with dozens of fintech companies on the brink of achieving "unicorn" status - that is, reaching a $1 billion valuation.

But even apart from the up-and-comers in the fintech space, there are plenty of tried-and-true fintech companies that have made businesses' and consumers' lives easier - including staples like PayPal (PYPL) - Get Report or Apple Pay (AAPL) - Get Report . And, according to TechCrunch, some 40 fintech companies are on the verge of reaching "unicorn" level with a $1 billion valuation - having raised $100 million last year in funding. 

Still, what are the top 10 fintech companies to watch in 2019, and which are the fastest growing? 

What Is Fintech?

Fintech is the common term used to refer to financial technology - which is an innovating industry that provides financial services with software, cloud or other technology. Fintech has both consumer and business applications, and ranges from cryptocurrency to mobile payments to health services.

Fintech has taken off in recent years, with U.S. fintech companies garnering some $12.4 billion in funding - up 43% from 2017. Additionally, the global mobile payments industry is reportedly set to surpass $1 trillion in 2019.

With both business-to-business and business-to-client applications, fintech has disrupted traditional industries, servicing an estimated near 2 billion people worldwide without traditional bank accounts. In addition, fintech has found applications in emerging technologies like artificial intelligence and blockchain.

As of 2019, there are 39 VC-backed fintech companies worth $1 billion - with a combined valuation of $147.4 billion, according to CB Insights.

Top 10 Fintech Companies in 2019

According to data from 2016, consumers use between one and three apps to manage their finances - and with the rise of other fintech companies in the cryptocurrency, human resources, insurance and investing spaces, there is no shortage of fintech startups disrupting traditional industries. So, which fintech companies are making a splash? 

1. Plaid

Co-founded by Zach Perret and William Hockey in 2013, Plaid allows various applications like payment apps to connect to users' bank accounts and helps speed up authentication. The company has certainly grown lately, helping connect apps like Betterment and Venmo with user's accounts. 

As of 2019, the fintech company was valued at $2.7 billion - and has integrated with some 10,000 banks. 

Additionally, as of January of this year, Plaid acquired Quovo, an investment data aggregation company, for around $200 million. 

2. Avant

With Avant, consumers can get loans from $2,000 to $35,000 fairly easily, as the company seeks to disrupt the lending industry. Founded by Paul Zhang, John Sun and Al Goldstein in 2012, the fintech company is now reportedly worth $2 billion. 

The online lending company boasts over 600,000 customers and generally caters to consumers with lower credit scores who might struggle getting loans otherwise, helping all consumers get instant loans online. 

3. Coinbase

For proponents of crypto, Coinbase is a popular platform to trade cryptocurrencies like bitcoin, ethereum and litecoin. The crypto exchange was founded in 2012 by Brian Armstrong and Fred Ehrsam, and is reportedly valued at $8 billion. 

Coinbase also recently acquired Earn.com for around $120 million, which allows bitcoin users to pay in bitcoin to connect with experts. 

The fintech exchange has been touted as the most "most beginner-friendly exchange," and has since reached "unicorn" status since its founding in 2012. 

4. Zenefits

Zenefits seeks to disrupt the human resources space by providing cloud-based human capital management services with a variety of applications and technology for businesses. Founded in 2013 by Parker Conrad and Laks Srini, the HR fintech company is now reportedly worth $2 billion.

The company seeks to reduce paperwork and increase efficiency with a plethora of tools that help businesses track payroll, benefits and other employee-related operations. 

5. Credit Karma

Credit Karma has seen enormous growth since its founding in 2007 - and is now worth some $4 billion. The fintech company, founded by Kenneth Lin, Nichole Mustard and Ryan Graciano, provides free credit scores and credit recommendations for consumers.

Unlike other sites, Credit Karma does not require users to register a credit card. As part of their services, Credit Karma also offers educational resources for their users - of which there are reportedly 85 million. 

6. Mint 

Intuit's (INTU) - Get ReportMint is a budgeting app that helps consumers track their expenses and income. 

Founded in 2006 by Aaron Patzer, Mint was sold to Intuit in 2009 for some $170 million just three years after its inception. 

Although now one of Intuit's brands, Mint has millions of users. The app also helps track users' bills and even provides a free credit score.

7. Robinhood

Having doubled their users from last year to around 6 million, Robinhood is an investment app that has taken the robo-adviser space by storm. 

Founded by Baiju Bhatt and Vladimir Tenev in 2013, Robinhood is now worth a reported $5.6 billion. The app boasts free trades of stocks and ETFs, as well as low minimums and even cryptocurrency. 

8. Acorns

Fintech startup Acorns is reportedly worth $860 million - and with good reason. The rapidly growing investment app provides their 4.5 million users with an easy way to invest spare change in the market - and also gives investors the opportunity to set automatic investment preferences. 

Founded in 2012 by Jeffrey James Cruttenden and Walter Wemple Cruttenden III, Acorns has nearly tripled its valuation since 2016. And, the app recently raised another $105 million in Series E funding

9. SoFi

Originally created for online student loan refinancing, SoFi has now branched into other fintech applications including robo-advising and insurance - coming with a hefty valuation of $4.4 billion.

Founded in 2011 by Mike Cagney, SoFi is short for "social finance" and targets primarily a millennial demographic with its various services. 

10. Circle

Having recently entered the crypto exchange space with its acquisition of Poloniex, Circle was founded in 2013 as a peer-to-peer payments service that is now worth around $3 billion.

The fintech company was founded by Jeremy Allaire and Sean Neville, and recently partnered with fellow fintech heavy-hitter Coinbase to create an ethereum blockchain-based USDC stable coin. Additionally, Circle allows users to send money as well as trade various cryptocurrencies.

Circle's backers include the likes of Goldman Sachs (GS) - Get Report , making up their roughly $250 million in funding

Fastest Growing Fintech Companies

Still, what are some of the fintech companies experiencing a meteoric rise? 

1. Stripe

Launched in 2011 by Patrick and John Collison as a payment processing service, Stripe is now worth a whopping $22.5 billion - and provides technology to the likes of Microsoft (MSFT) - Get Report and Amazon (AMZN) - Get Report

According to Forbes this year, the fintech company recently announced new products including "credit card issuing technology, point-of-sale software and a billing platform for subscription businesses." 

Additionally, the company provides services that help companies manage finances and prevent against fraud, among other apps - using a cloud-based infrastructure. Notable companies using Stripe's technology include Salesforce (CRM) - Get Report , Spotify(SPOT) - Get Report and Alphabet (GOOG) - Get Report

The company boasts nine global offices and millions of users in 2019. 

2. Stash

Fintech startup Stash provides consumers with an opportunity to get into micro investing - or, investing small amounts of money into the stock market. Founded in 2015 by Ed Robinson, Brandon Krieg and David Ronick, Stash targets beginner investors by providing easy and simple access to investment vehicles like ETFs with low minimums and service fees.

According to reports, Stash secured a Series D funding round of $37.5 million in February of last year. Although competition in the investment app space is fierce, Stash has managed to continue growing in the robo-advising industry. 

3. Oscar

Oscar Health was founded in 2013 by Josh Kushner, Mario Schlosser and Kevin Nazemi to disrupt the health insurance industry and provide easier access to more healthcare options.

The fintech health company is worth an estimated $3.2 billion as of late 2018 - with some 250,000 members in 2019. The company recently raised some $375 million in investment from Alphabet. Additionally, Oscar offers coverage to users in New York, California, Texas, New Jersey, Ohio and Tennessee, soon to be followed by Arizona, Florida and Michigan in 2019. 

According to co-founder Schlosser, the company was founded on the premise of disrupting a largely stagnant industry.

Biggest Fintech Companies 

While there are plenty of up-and-coming fintech companies to watch in 2019, there are several mammoth fintech companies that have led (and continue leading) the way in innovation (not to mention market cap). 

1. PayPal

No fintech discussion is complete without mentioning PayPal - the mobile payments company that boasts a market cap of $113 billion. 

As a long time staple of the fintech space, PayPal was founded way back in 1998 by the likes of Peter Thiel and Tesla's (TSLA) - Get Report Elon Musk, among others. Since its inception, the payments app has grown exponentially, and acquired fellow popular payments app Venmo in 2014 under Braintree for $800 million.

Additionally, PayPal stock has reportedly shown annual returns of around 35.2%. 

2. Alibaba

Mega Chinese fintech company Alibaba (BABA) - Get Report  is dominating the industry. 

Founded back in 1999 by Jack Ma among several others, the Chinese fintech company has branched out into several different industries including the payments service with AliPay - which boasts some 520 million users. Additionally, Ant Financial was founded in 2014 and provides financial services. 

Alibaba has a massive market cap of over $468 billion. 

3. Fiserv/First Data

The two payments companies rung in 2019 with a bang - and a mega fintech M&A deal.

Fiserv (FISV) - Get Report and First Data (FDC) - Get Report are set to become a combined $22 billion company, servicing the fintech payments space, announced in January.

Fiserv is a company that sells various technology to banks or credit unions, and First Data is a payment processing service. 

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