Zero. That's how many packets slipped past my kill switch during three straight days of deliberately yanking my connection mid-stream, once standing in Discovery Park with my phone on a hotspot just to see if cellular made the leak numbers worse. It didn't. That's the same instinct behind every speed test on this site: chase the actual reason your Netflix or Hulu stream buffers, not the one you'd assume.
Quick disclosure before the packet captures start: a handful of the links below are affiliate links, and I earn a commission if you sign up through one, at no extra cost to you. I've paid for every subscription mentioned here out of my own pocket (my partner has opinions about how much of our home network has quietly become a testing rig, and she's not wrong) — everything below comes from my own recurring comparisons, not a press kit. If you just want the fastest pipe for a 4K habit, NordVPN has stayed at the top of my charts more consistently than anything else I've run.
The Real Reason Your Stream Buffers Isn't Encryption
The common assumption goes like this: a VPN scrambles every packet, scrambling takes processing time, so of course your stream buffers more with a VPN turned on. It's a tidy theory, and it's wrong often enough that I stopped trusting it as a diagnosis. Modern encryption on a phone or laptop built in the last several years barely registers as overhead (the actual math takes microseconds). The stall almost always traces back to something else: a congested server, a route that hops through three more cities than it needs to, or an ISP quietly deciding video traffic gets a smaller lane during peak hours.
My former teammate Ezra Pontis, who cares about latency the way some people care about their fantasy football lineup, put it to me bluntly once: encryption overhead is a rounding error next to a bad server pick. That stuck with me, mostly because he's usually right about this stuff. Buffering that only shows up during video, and not during something like a large file download, points to a shaping rule your provider applies rather than a real bandwidth ceiling — a testable distinction, not a hunch you talk yourself into.
The Actual Floor Your Connection Needs to Hit
Buying a VPN often looks like shopping for a wireless router: you chase the biggest number on the box and assume that's what you'll get. Streaming doesn't work that way; it's not the peak that matters but the floor. To hold 4K resolution on Netflix, you need a steady 25 Mbps, not a burst to 25 Mbps once every few seconds. Drop below that floor even briefly and the app downscales you to 1080p, or worse, hits you with the spinning wheel.
Battery life is the other cost nobody mentions in the marketing copy. A heavier protocol chews through more processing power than a leaner one, and while that's invisible on a desktop plugged into the wall, it's very noticeable a few episodes into a Hulu binge on a tablet with the battery already complaining. Picking the right protocol for the device you're actually streaming on matters more than picking the "fastest" VPN in the abstract (I go deep on that comparison in 30 Days, 5 VPNs, and 450 Speed Tests), but this piece sticks to what actually changes a Friday-night stream.
NordVPN vs. ExpressVPN: What the Speed Tests Actually Showed
Toggling between NordVPN and ExpressVPN for a stretch this spring, the gap wasn't subtle. NordVPN's NordLynx protocol — its version of WireGuard — held well above the 240 Mbps mark against my gigabit baseline, consistently, not just on a good day. It sits on the more affordable end of this list, which is a big part of why it's stayed my top pick, though the map-based server interface gets cluttered when you're just trying to find one specific city.
Then there's ExpressVPN, the priciest option in this group by a noticeable margin. Its Lightway protocol is the most battery-friendly one I've tested, and the whole thing behaves like a cloud storage plan that just works without you thinking about it. Someone who wants to set a VPN once and never open the settings menu again will be happier with Express than with Nord, even paying more for the privilege. It also edges out most competitors on latency if gaming matters to you — I cover that separately in my Best VPN for Online Gaming piece.
CyberGhost's Streaming Servers and the Netflix Blacklist Problem
Leaning into CyberGhost VPN for a while changed how I think about this. Instead of making you guess which server unblocks what, it has a dedicated "For Streaming" tab with servers labeled by platform, backed by dedicated IP pools that are less likely to land on Netflix's anti-VPN blacklist in the first place. That's a different feature than raw server count — a provider advertising dozens of countries doesn't help if only a handful of those exit IPs are still unblocked, since streaming catalogs are keyed to the specific IP you land on, not the country label in the app.
Domestically, this has been my most reliable pick for zero-buffering sessions during a lazy weekend afternoon, which surprised me some, since I expected the budget-friendlier option to be the first to choke under load. CyberGhost is owned by Kape Technologies — the same parent company as ExpressVPN — worth knowing, though it doesn't change how the app performs day to day. Connections to servers overseas showed real dips in testing, but for Netflix and Hulu from a U.S. connection, that hasn't mattered much.
Should You Bother With Private Internet Access or Surfshark?
Tinkering with MTU settings and picking an exact encryption level is either your idea of fun or it isn't, and Private Internet Access is built for the people who say yes. Its apps are fully open-source, which appeals to the part of my brain that reads other people's code for fun, and I've recommended it before in my Best No Logs VPN for Developers piece, if an independently verifiable no-logs claim matters more to you than raw streaming convenience. For pure Netflix-and-Hulu streaming, though, it's inconsistent — expect to cycle through a couple of "US East" servers before landing on one that hasn't been flagged.
Surfshark solves a different problem entirely: unlimited devices on a single account. Between laptops, phones, a tablet, and a couple of smart TVs in most households, that adds up fast, and Surfshark handles the load better than its budget price point would suggest. Its CleanWeb feature blocks a decent share of the trackers that streaming sites love to embed, too. Just budget for the jump after the introductory period — like most subscription software, the early pricing isn't the pricing you keep long-term.
What Actually Broke During My Testing
Long before I trusted any commercial VPN for this, I ran my own WireGuard server on a cheap VPS, figuring I'd cut out the middleman entirely. It worked right up until I needed to print something or cast to the living room TV — the tunnel routed every packet through the VPS, and my laptop couldn't see a single device on my own network anymore. That's split tunneling in a nutshell: without a way to carve out exceptions for local traffic, a "more private" setup can turn your own house into a foreign network.
Server load matters more than distance, which is the other thing that surprised me. A busy server one state over was consistently slower than an idle one much farther out, which is why I favor apps like NordVPN and CyberGhost that show a load percentage before you connect (it saves the trial-and-error loop of connecting, disconnecting, and reconnecting while your coffee goes cold). Waverly Obasi, a fellow enthusiast from the VPN subreddit I occasionally moderate, ran a near-identical test on her own connection and insisted on matching the time of day and server load before comparing numbers with mine. That kind of discipline is exactly what separates a real diagnosis from "my VPN feels slow today." And a kill switch isn't optional in any of this: if the VPN drops and your TV reverts to your real IP mid-stream, Netflix can lock the account to a different region until you clear the app's cache.
So Which VPN Actually Stops the Buffering Wheel?
For the fastest raw speeds on a 4K habit, NordVPN is still the one I'd point people toward first — consistent results, no drama. Anyone who wants to audit the code and tune every setting gets the most for the least with Private Internet Access, provided they don't mind a bit of hands-on setup.
Everyone else who just wants to hit play and watch something in 4K without narrating the buffering wheel to themselves should grab CyberGhost VPN instead — cheap enough to forget you're paying for it, fast enough that you never have to think about it. The 45-day money-back window is a reasonable safety net if it doesn't get along with your specific smart TV. Whichever one you pick, the fix for a stuttering stream is almost never "more encryption horsepower" — it's a server with room to breathe and a provider honest about where its exit IPs actually work.