SIM Cards for Internet Connectivity: Data, Costs & Calculator

Managed SIM connectivity for internet access and backup

Use a compatible cellular router to connect a temporary site, remote office or backup internet link. The plan must accommodate the combined traffic of users and applications; coverage and available capacity also affect the experience.

Shared data and contract options

Seneca’s fleet planner provides indicative pricing for multi-network SIMs sharing a monthly data pool, with PAYG and 24-month options. Check coverage, device compatibility, usage limits and final terms before activation. Onboarding is additional.

SIM cards for Broadband backup

A cellular router can take over when a fixed broadband connection fails. Standby checks use data even when the backup connection is rarely active. This example assumes mostly standby with limited failover use; a prolonged outage carrying live traffic transfers far more, so size it from the expected outage hours and the applications that stay online.

Data requirements for Broadband backup

Budget for a realistic outage period and decide which applications may use the backup link. Test the failover process and available capacity.

Worked data and cost example

Illustrative usage: 1 router SIM, with an assumed 20 GB of application traffic per SIM in the month. Add 1 GB per SIM for other traffic and 20% spare capacity. The resulting fleet data budget is 25.2 GB. A 25.5 GB shared pool for this fleet is priced by the fleet planner at £76.85 monthly on PAYG (the 24-month term for this size is priced on application) including VAT.

SIM cards for Construction-site internet

A cellular router can connect site offices and work applications while fixed connectivity is unavailable. This example assumes tightly controlled light use; several users running video meetings, drawing downloads and cloud synchronisation need considerably more.

Data requirements for Construction-site internet

Include drawings, video meetings, cloud synchronisation and staff devices. Estimate camera traffic separately if CCTV shares the connection.

Worked data and cost example

Illustrative usage: 1 router SIM, with an assumed 60 GB of application traffic per SIM in the month. Add 1 GB per SIM for other traffic and 20% spare capacity. The resulting fleet data budget is 73.2 GB. A 73.5 GB shared pool for this fleet is priced by the fleet planner at £212.06 monthly on PAYG (the 24-month term for this size is priced on application) including VAT.

SIM cards for Event Wi-Fi

Cellular backhaul can support registration systems, staff connectivity or guest Wi-Fi at temporary events. Event data depends heavily on attendance and duration; size it from the expected concurrent users and session length rather than this illustrative figure.

Data requirements for Event Wi-Fi

Estimate peak concurrent users as well as total data. Check venue coverage and whether the event load affects available capacity.

Worked data and cost example

Illustrative usage: 1 router SIM, with an assumed 80 GB of application traffic per SIM in the month. Add 1 GB per SIM for other traffic and 20% spare capacity. The resulting fleet data budget is 97.2 GB. A 97.5 GB shared pool for this fleet is priced by the fleet planner at £279.67 monthly on PAYG (the 24-month term for this size is priced on application) including VAT.

SIM cards for Remote-office connectivity

A router SIM can connect a small remote office for business applications, collaboration and remote support. This example assumes a single light user with controlled updates; a multi-user office with routine video calls — around 2 GB per hour of 720p calling — needs more.

Data requirements for Remote-office connectivity

Include video meetings, backups, updates and large file transfers. Check VPN and application compatibility.

Worked data and cost example

Illustrative usage: 1 router SIM, with an assumed 50 GB of application traffic per SIM in the month. Add 1 GB per SIM for other traffic and 20% spare capacity. The resulting fleet data budget is 61.2 GB. A 61.5 GB shared pool for this fleet is priced by the fleet planner at £178.26 monthly on PAYG (the 24-month term for this size is priced on application) including VAT.

SIM cards for Boats and campervans

A cellular router can provide internet where supported mobile networks are available during travel. This example assumes occasional browsing; routine streaming or remote working transfers considerably more.

Data requirements for Boats and campervans

Confirm permitted countries, roaming terms, router bands and antenna arrangements. Streaming and software updates can quickly increase usage.

Worked data and cost example

Illustrative usage: 1 router SIM, with an assumed 30 GB of application traffic per SIM in the month. Add 1 GB per SIM for other traffic and 20% spare capacity. The resulting fleet data budget is 37.2 GB. A 37.5 GB shared pool for this fleet is priced by the fleet planner at £110.65 monthly on PAYG (the 24-month term for this size is priced on application) including VAT.

SIM plan pricing and worked fleet examples

Seneca’s fleet planner uses a shared data pool that resets monthly. The examples below are produced by the same pricing engine as Seneca’s live fleet planner (checked 5 October 2026); they are indicative, not guaranteed tariffs for every configuration.

PAYG is displayed as monthly rolling with 30 days’ notice. The 24-month option is a commitment; where the planner shows price on application, request a quote. The planner lists additional usage at £4 per GB including VAT and notes that onboarding is additional.

PAYG examples also show a one-off SIM card charge; the 24-month option shows the SIM card included. The monthly table excludes one-off charges. Verify current pricing, coverage, usage limits and order-form terms in the Seneca fleet planner before activation.

How the data estimate is calculated

Video, reports and monthly application traffic

Video is estimated at 0.45 GB per hour for each 1 Mbps transmitted stream. Reporting traffic uses transmitted KB per record × reports per day × days ÷ 1,000,000 to give decimal GB. Router and media-download scenarios use a monthly GB estimate entered by you. These models assume the selected pattern is consistent during the month.

Spare capacity and real usage

Add maintenance, heartbeats, reconnects and updates as other traffic. Spare capacity increases the recommended data budget. Use transmitted record sizes rather than payload-only sizes where possible, and validate the estimate against a pilot or router usage records. Motion clips are capped at 24 hours per camera per day; remote viewing is counted separately. Continuous cloud mode assumes viewing happens through the cloud and does not create another SIM stream.

Plan your internet connectivity SIM service

Confirm equipment and operating requirements

Send the router model, locations or travel routes, SIM count and expected monthly traffic. For backup links, include the anticipated outage duration and which applications will remain active. For events, include concurrent users and peak upload requirements.

Choose the data pool and contract term

Use the calculator to estimate combined traffic, including other data and spare capacity. Check current plan prices in Seneca’s fleet planner and compare the term that suits your deployment. The calculator’s annual figure covers 12 months of running cost; it does not represent the total commitment of a 24-month contract.

Confirm activation and one-off costs

Request confirmation of onboarding, SIM card charges, supported coverage and any platform or remote-access requirements. Hardware, installation, monitoring subscriptions and specialist communication functions are not included in the running-cost estimates shown here.

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