VoIP • Mobile call quality

How to get the best call quality over LTE

Q: Is VoLTE better than VoIP over LTE?

For pure mobile-to-mobile calls, VoLTE usually sounds better because the operator carries it as priority HD voice. VoIP over LTE gives you control and works with a business phone system, but you have to tune signal, QoS and codec to match VoLTE quality.

Q: How much bandwidth does an LTE call use?

A single G.711 call uses roughly 100 kbps in each direction, including overhead. Lower-bandwidth codecs such as Opus or G.729 use less, which helps on weaker links. Size your connection for the number of calls you run at once, not the average.

Q: Why do my LTE calls break up at certain times of day?

An LTE cell is shared among everyone nearby, so it can congest at busy hours. Enabling QoS on your router prioritises voice, and an external antenna pointed at a less-loaded tower can help. If it persists, the cell may be oversubscribed in your area.

Q: Does an external antenna really improve call quality?

Yes, where signal is marginal. A directional or panel antenna aimed at the nearest tower raises signal strength and stability, which directly reduces the retransmissions that cause robotic, choppy audio. It is one of the highest-impact fixes on LTE.

Q: Can I run a whole office phone system over LTE?

Yes, many SMEs do, especially where fibre has not arrived. The keys are a strong stable signal, a router that prioritises voice, and sizing the link for your busy-hour call count. For larger fixed offices, fibre still gives steadier quality.

Q: What latency and jitter should I aim for?

Keep one-way latency under 150 ms, the ITU-T G.114 guideline for natural conversation, and jitter under about 30 ms. Packet loss above roughly 1% starts to drop words. Most router and softphone diagnostics show these figures live.

When your calls ride mobile data instead of fibre, quality is won or lost on signal, jitter and codec choice. Here is what actually moves the needle, and the order to fix it in.

Last verified 17 June 2026
By the WhichVoIP editorial team
7 min read

<150 msOne-way latency target for natural conversation

<30 msJitter ceiling before audio breaks up

<1%Packet loss before words drop

~100 kbpsPer call on the G.711 codec

The short answer

How do I get the best call quality over LTE?

Start with signal: place the device or router where it gets the strongest, most stable LTE reception, ideally with an external antenna. Then protect the call from congestion with a router that prioritises voice, keep latency under 150 ms and jitter under 30 ms, and choose a codec that suits your bandwidth. Fix signal first; everything else is secondary.

Latency target for natural two-way speech (ITU-T G.114)

Jitter ceiling before audio garbles

Packet loss your ear starts to notice

Bandwidth one G.711 call needs each way

Business Professional Making A Clear Mobile Call Over An Lte Network — On LTE, the single biggest lever on call quality is signal strength and stability, not the phone or the app.

VoLTE and VoIP over LTE are not the same thing

Two different things get called “calling over LTE”, and the quality levers differ for each.

VoLTE (Voice over LTE) is the carrier’s own HD voice service running on the mobile network. The call is carried as priority traffic by the operator, so it generally sounds excellent where there is good coverage. You do not configure it beyond enabling it on the handset.

VoIP over LTE is your business phone system (a softphone app or an LTE router feeding desk phones) sending voice as data across the same mobile network, but with no special priority from the carrier. This is what most SMEs mean when they run a cloud phone system on an LTE connection, and it is the one you can tune.

✓

Bottom line: if you only need mobile-to-mobile calls, enable VoLTE and you are done. If you run a business phone system over an LTE data connection, the rest of this guide is for you.

What actually decides LTE call quality

Four measurable things sit between a clean call and a choppy one. Fix them in this order.

The four levers, in priority order

Signal strength and stability

Weak or fluctuating signal forces the network to retransmit packets, which shows up as gaps and robotic audio. Check the RSRP and SINR figures in the router or handset diagnostics. A strong, steady signal in one spot beats a stronger signal that drifts as you move around.

Jitter and latency

Voice needs packets to arrive evenly. Jitter, the variation in arrival time, is what a jitter buffer smooths out, but only up to a point. Keep one-way latency under 150 ms (the ITU-T G.114 guideline for natural conversation) and jitter under about 30 ms.

Congestion and codec

An LTE cell is shared, so quality can dip at busy times of day. A router that prioritises voice traffic protects calls when the link is busy. Codec choice is the final lever: G.711 gives the cleanest audio at roughly 100 kbps each way, while Opus or G.729 use less bandwidth on weaker links at a small quality cost.

Seven steps to a cleaner LTE call

Work top to bottom. Most quality problems are solved by the first three.

Find the best signal spotMove the LTE router to a window or higher floor and watch the RSRP/SINR readout settle on its best stable value.

Add an external antennaA directional or panel antenna aimed at the nearest tower lifts a marginal signal into reliable territory, especially in steel-roofed offices.

Prioritise voice on the routerEnable QoS so voice packets are sent ahead of downloads and video, protecting calls during busy periods.

Use a wired handset where you canPlug desk phones into the router by cable rather than adding a second Wi-Fi hop that introduces its own jitter.

Match the codec to the linkStay on G.711 on a strong signal; let the system fall back to Opus or G.729 when bandwidth is tight.

Cap concurrent callsEach call needs its own headroom. Size the connection for your busy-hour call count, not the average.

Test, then re-test from the real deskRun a quality test from where staff actually sit, at a busy time, not from the best spot in the building.

On a mobile connection, signal is the call. Fix where the antenna sits before you blame the app, the phone or the provider.

WhichVoIP editorial view

Smartphone Showing Mobile Signal Bars And Hd Voice Call Settings — Check the RSRP and SINR readout before changing anything else; a steady signal is worth more than a strong one that drifts.

VoLTE vs VoIP over LTE vs VoIP over fibre

LTE can carry good business calls, but a wired connection still gives you the most consistent quality.

Factor	VoLTE (carrier)	VoIP over LTE	VoIP over fibre
Who controls priority	The mobile operator	You, via router QoS	You, end to end
Best-case quality	HD, excellent	Good with tuning	HD, very stable
Sensitive to congestion	Low	Higher at busy hours	Lowest
Tunable by you	No	Yes	Yes
Best use	Mobile staff	Sites without fibre	Fixed offices

Watch: LTE is an excellent backup and a fine primary link where fibre has not arrived, but if a fibre line is available at the premises it will almost always give steadier business call quality.

Our verdict

You can run clean business calls over LTE. The quality you get is decided mostly by signal, then by how well your router protects voice from congestion, and only last by the codec. Get the antenna in the right place, switch on QoS, and size the link for your busy-hour call count, and an LTE connection will carry calls that most callers cannot tell from fibre.

Our recommendation: treat LTE as a strong option where fibre is absent or as a failover, fix signal first, and reserve fibre for fixed offices that need the steadiest possible quality.

Comparing VoIP options for an LTE or fibre site?

Tell us how your team connects and we will match you with providers that suit a mobile-first or fixed-line setup.

Get matched with providers
Fix choppy calls

Frequently asked questions

Is VoLTE better than VoIP over LTE?

For pure mobile-to-mobile calls, VoLTE usually sounds better because the operator carries it as priority HD voice. VoIP over LTE gives you control and works with a business phone system, but you have to tune signal, QoS and codec to match VoLTE quality.

How much bandwidth does an LTE call use?

A single G.711 call uses roughly 100 kbps in each direction, including overhead. Lower-bandwidth codecs such as Opus or G.729 use less, which helps on weaker links. Size your connection for the number of calls you run at once, not the average.

Why do my LTE calls break up at certain times of day?

An LTE cell is shared among everyone nearby, so it can congest at busy hours. Enabling QoS on your router prioritises voice, and an external antenna pointed at a less-loaded tower can help. If it persists, the cell may be oversubscribed in your area.

Does an external antenna really improve call quality?

Yes, where signal is marginal. A directional or panel antenna aimed at the nearest tower raises signal strength and stability, which directly reduces the retransmissions that cause robotic, choppy audio. It is one of the highest-impact fixes on LTE.

Can I run a whole office phone system over LTE?

Yes, many SMEs do, especially where fibre has not arrived. The keys are a strong stable signal, a router that prioritises voice, and sizing the link for your busy-hour call count. For larger fixed offices, fibre still gives steadier quality.

What latency and jitter should I aim for?