It said that those virtual coins could then be used to buy stuff from the 26 million sellers that accept PayPal.
Over the next few weeks, PayPal plans to phase out buying options in the US, with the complete release expected early next year.
Along with the news, Bitcoin prices rose, breaking the $12,000 mark (£9,170).
Ethereum, Litecoin and Bitcoin Cash (a spin-off from Bitcoin) will be the other cryptocurrencies to be added first.
The company said that anything could be processed “directly inside the PayPal digital wallet”.
Stocks of Penny
Cryptocurrencies, partially due to the rapid shift in prices they can encounter compared to conventional state-backed currencies, have remained a niche payment form. That has made them popular with certain kinds of investors.
PayPal said it was aimed at “growing the awareness and acceptance of cryptocurrencies by customers.”
“PayPal will provide educational content to account holders as part of this offering to help them understand the world of cryptocurrencies,” it said.
But David Gerard, author of the 50 Foot Blockchain Attack and the forthcoming Libra Shrugged: How Facebook was trying to take over the capital, said that “a crypto day-trading market” was represented by PayPal.
“I am at a loss as to who the PayPal market as a crypto-exchange is,” he said.
But with Bitcoin, whose unpredictable and less well-regulated nature was like “gambling on penny stocks,” he compared it to playing the stock market.
“He warned,” Have a flutter, drop $10 on it, you’ll learn things that you’re not going to learn any other way — but you’re gambling.
He said there were “a lot of big players manipulating the price,” and they risked losing their money to ordinary citizens.
“Beyond current crypto holders, I don’t expect much of a demand for this … I’m puzzled why PayPal will sell this, and it’s not obvious what they’re trying to do here,” he said.
“At PayPal, there needs to be someone who is really interested in cryptocurrencies,” he said.
Other payment companies, including Square’s Cash app and Revolut, have offered cryptocurrencies for sale. Yet PayPal has the world’s largest retailer network.
When using the virtual coins, PayPal will translate the cryptocurrency into the relevant national currency, so the paying company will never obtain the virtual coins-only the right sum of pounds or dollars.
PayPal said the system meant “safe value and no incremental fees.”
But using Bitcoin to pay ordinary merchants is not due until “early 2021.”
The unpredictable prices of Cryptocurrencies — along with their past usage as a less traceable payment mechanism for illicit purposes — have led to numerous calls for regulation.
PayPal was given authorization from the New York State Department of Financial Services to operate under a conditional “Bitlicense,” the first such license given.
First, the service will operate with an established US cryptocurrency provider, Paxos Trust Business.
But it’s not PayPal’s first region venture.
Once a partner in Facebook’s digital currency Libra, the company became the first to pull out of the partnership just months after it was revealed.
The scheme was controversial, drawing scrutiny from multi-country financial regulators.
Earlier this year, Facebook was reported to “rethink” the resistance theory.