diff --git a/include/osmocom/gsm/sysinfo.h b/include/osmocom/gsm/sysinfo.h
index c7972f4..f3e0f22 100644
--- a/include/osmocom/gsm/sysinfo.h
+++ b/include/osmocom/gsm/sysinfo.h
@@ -1,6 +1,8 @@
 #pragma once
 
 #include <stdbool.h>
+
+#include <osmocom/core/defs.h>
 #include <osmocom/core/utils.h>
 #include <osmocom/gsm/protocol/gsm_04_08.h>
 
@@ -66,7 +68,8 @@
 extern const struct value_string osmo_sitype_strs[_MAX_SYSINFO_TYPE];
 int osmo_earfcn_add(struct osmo_earfcn_si2q *e, uint16_t arfcn, uint8_t meas_bw);
 int osmo_earfcn_del(struct osmo_earfcn_si2q *e, uint16_t arfcn);
-size_t osmo_earfcn_bit_size(const struct osmo_earfcn_si2q *e);
+size_t osmo_earfcn_bit_size(const struct osmo_earfcn_si2q *e) OSMO_DEPRECATED("Use osmo_earfcn_bit_size_ext()instead.");
+size_t osmo_earfcn_bit_size_ext(const struct osmo_earfcn_si2q *e, size_t offset);
 void osmo_earfcn_init(struct osmo_earfcn_si2q *e);
 uint8_t osmo_sitype2rsl(enum osmo_sysinfo_type si_type);
 enum osmo_sysinfo_type osmo_rsl2sitype(uint8_t rsl_si);
diff --git a/src/gsm/libosmogsm.map b/src/gsm/libosmogsm.map
index 97fd2b4..8fb9878 100644
--- a/src/gsm/libosmogsm.map
+++ b/src/gsm/libosmogsm.map
@@ -48,6 +48,7 @@
 osmo_earfcn_add;
 osmo_earfcn_del;
 osmo_earfcn_bit_size;
+osmo_earfcn_bit_size_ext;
 osmo_earfcn_init;
 
 gprs_cipher_gen_input_i;
diff --git a/src/gsm/sysinfo.c b/src/gsm/sysinfo.c
index 3ec5444..b5ebd57 100644
--- a/src/gsm/sysinfo.c
+++ b/src/gsm/sysinfo.c
@@ -151,15 +151,30 @@
  */
 size_t osmo_earfcn_bit_size(const struct osmo_earfcn_si2q *e)
 {
+	return osmo_earfcn_bit_size_ext(e, 0);
+}
+
+/*! \brief Return number of bits necessary to represent earfcn struct as
+ *  Repeated E-UTRAN Neighbour Cells IE from 3GPP TS 44.018 Table 10.5.2.33b.1
+ *  \param[in,out] e earfcn struct
+ *  \param[in] offset into earfcn struct: how many EARFCNs to skip while estimating size
+ *  \returns number of bits
+ */
+size_t osmo_earfcn_bit_size_ext(const struct osmo_earfcn_si2q *e, size_t offset)
+{
 	/* 1 stop bit + 5 bits for THRESH_E-UTRAN_high */
-	size_t i, bits = 6;
+	size_t i, bits = 6, skip = 0;
 	for (i = 0; i < e->length; i++) {
 		if (e->arfcn[i] != OSMO_EARFCN_INVALID) {
-			bits += 17;
-			if (OSMO_EARFCN_MEAS_INVALID == e->meas_bw[i])
-				bits++;
-			else
-				bits += 4;
+			if (skip < offset)
+				skip++;
+			else {
+				bits += 17;
+				if (OSMO_EARFCN_MEAS_INVALID == e->meas_bw[i])
+					bits++;
+				else
+					bits += 4;
+			}
 		}
 	}
 	bits += (e->prio_valid) ? 4 : 1;